Co-reporter:Chen Zhang, Rahul S. Patil, Charles L. Barnes, and Jerry L. Atwood
Crystal Growth & Design September 6, 2017 Volume 17(Issue 9) pp:4541-4541
Publication Date(Web):July 24, 2017
DOI:10.1021/acs.cgd.7b00968
We present here the preparation of anionic dimeric and hexameric C-alkylpyrogallol[4]arene nanocapsules by attaching multiple nitrate ions to the nanocapsule surface via metal coordination. These anionic nanocapsules can be utilized for encapsulation of cationic guest molecules and have potential applications in catalysis, sensing, and biomedicine. This study demonstrates that the surface functionalization may act as an effective method to tailor and introduce new properties to metal–organic nanocapsules.
Co-reporter:Asanka S. Rathnayake, Charles L. Barnes, and Jerry L. Atwood
Crystal Growth & Design September 6, 2017 Volume 17(Issue 9) pp:4501-4501
Publication Date(Web):August 14, 2017
DOI:10.1021/acs.cgd.7b00597
A metal–organic nanocapsule consisting of 24 Zn2+ ions and six pyrogallol[4]arene units has been synthesized and structurally characterized. All the Zn2+ ions seaming the nanocapsule are disordered over two positions forming concave distortions on the framework.
Co-reporter:Shan Jiang, Rahul S. Patil, Charles L. Barnes, and Jerry L. Atwood
Crystal Growth & Design August 2, 2017 Volume 17(Issue 8) pp:4060-4060
Publication Date(Web):June 30, 2017
DOI:10.1021/acs.cgd.7b00691
Cocrystals formed from macrocyclic compounds such as calixarenes are particularly useful for understanding various host–guest interactions and solid state properties. Resorcinarenes, a subclass of calixarenes, are also useful for the construction of cocrystalline materials because of their unique bowl shape, decorated with eight hydroxyl groups. Here we investigate the separation of hexameric C-ethylresoricn[6]arene from its tetrameric homologues C-ethylresorcin[4]arene via cocrystallization with 4,4′-bipyridine (Scheme 1). The effect of the stoichiometric ratio of the components and the solvent of crystallization on the separation of macrocycles and on the formation of a particular cocrystal is also discussed.
Co-reporter:Rahul S. Patil, Chen ZhangCharles L. Barnes, Jerry L. Atwood
Crystal Growth & Design 2017 Volume 17(Issue 1) pp:
Publication Date(Web):December 12, 2016
DOI:10.1021/acs.cgd.6b01464
Among the class of porous crystalline materials, supramolecular organic frameworks (SOFs) have proven to be of great importance due to their potential applications in gas sorption/separation, catalysis, and nanotechnology. Herein, we present construction and characterization of two novel SOFs based on a large macrocyclic compound, noria, and linker molecules such as 4,4′-bypyridine and 1,2-bis(4-pyridyl)ethylene. Use of bipyridine type spacer molecules can partially or completely replace typical O–H···O intermolecular hydrogen bonds between noria molecules by O–H···N interactions. Due to the moderate length difference, the two spacer molecules lead to the assembly of 1D chains and 2D networks, respectively.
Co-reporter:Chen Zhang;Kanishka Sikligar;Rahul S. Patil;Charles L. Barnes;Simon J. Teat
Chemical Communications 2017 vol. 53(Issue 69) pp:9613-9615
Publication Date(Web):2017/08/24
DOI:10.1039/C7CC06099H
The solvothermal synthesis of two M7L2 metal–organic nanocapsules from C-alkyl pyrogallol[3]resorcin[1]arene is reported. Using mixed macrocycles as building blocks shows great potential in the discovery of new metal–organic nanocapsules with novel properties.
Co-reporter:Chen Zhang;Rahul S. Patil;Charles L. Barnes
Chemical Communications 2017 vol. 53(Issue 89) pp:12144-12147
Publication Date(Web):2017/11/07
DOI:10.1039/C7CC07390A
Enhancing hierarchical structural complexities of metal–organic nanocapsules is an effective way of introducing new functions and properties. Herein, we present the synthesis of novel magnesium-seamed C-alkylpyrogallol[4]arene nanocapsules with hierarchical structural complexity via both exterior and endohedral functionalization. The exterior functionalization is realized by using a variety of covalently modified pyrogallol[4]arene ligands, while the endohedral functionalization is achieved via coordination-driven self-assembly. Especially, functionalization of nanocapsule interior by attaching a proline hexad via metal coordination will shed light to the design and synthesis of metal–organic species with heteroligated architectures.
Co-reporter:Chen Zhang;Rahul S. Patil;Tao Li;Charles L. Barnes
Chemical Communications 2017 vol. 53(Issue 31) pp:4312-4314
Publication Date(Web):2017/04/13
DOI:10.1039/C7CC01208J
The solvothermal synthesis of a metal-seamed hexameric nanocapsule from pyrogallol[4]arenes and magnesium is reported. The unique non-toxic and biocompatible nature of divalent magnesium cations in addition to the large inherent cavities make these nanocapsules promising for potential application in biomedicine. In addition, we show that these nanocapsules can form cocrystals with pyridine molecules through hydrogen bonding, which sheds light to cocrystallization of supramolecular nanocapsules with small pharmaceutics.
Co-reporter:Harshita Kumari, Steven R. Kline, Stuart R. Kennedy, Christopher Garvey, Colin L. Raston, Jerry L. Atwood and Jonathan W. Steed
Chemical Communications 2016 vol. 52(Issue 24) pp:4513-4516
Publication Date(Web):25 Feb 2016
DOI:10.1039/C6CC00171H
Vortex fluidic mediated shearing of supramolecular gels in thin films leads to complete disruption of fluorous bis-urea derived gels. Hydrocarbon analogues however, are only partially disrupted, which emphasizes the resistance of non-fluorous bis-urea gelators towards shear. The gel structures have been studied by combining the thin film shearing with small angle neutron scattering. This technique represents a novel approach to study the effects of external stimuli on self-assembled supramolecular gel networks.
Co-reporter:Harshita Kumari, Collin M. Mayhan, Charles L. Barnes, Carol A. Deakyne and Jerry L. Atwood
CrystEngComm 2016 vol. 18(Issue 26) pp:4909-4913
Publication Date(Web):16 May 2016
DOI:10.1039/C6CE00639F
The synthesis, the single-crystal X-ray structure, and a metal-exchange study of a zinc-seamed C-hexylpyrogallol[4]arene/PgC6Zn dimer are reported. The packing arrangement of the PgC6Zn dimer shows interdigitation between the C-hexyl tails. Neighboring dimeric nanocapsules are slightly offset with respect to each other, with CH⋯π interactions between the hexyl tails and the external pyridine ligands. In situ metal exchange with nickel nitrate does not result in expulsion of zinc metal centers from a pre-formed dimer, a result suggesting a framework robustness that may make formation of (magnetically interesting) mixed-metal dimers difficult. The suggested robustness of zinc-seamed pyrogallol[4]arene-based dimers is supported by quantum chemical calculations on related PgC0Zn and PgC3Zn dimers.
Co-reporter:Constance R. Pfeiffer, Kyle A. Feaster, Scott J. Dalgarno and Jerry L. Atwood
CrystEngComm 2016 vol. 18(Issue 2) pp:222-229
Publication Date(Web):11 Nov 2015
DOI:10.1039/C5CE01792K
Seven aryl-substituted pyrogallol[4]arenes and six aryl-substituted resorcin[4]arenes were synthesized through the acid catalyzed reaction of either pyrogallol or resorcinol with a specific alkoxybenzaldehyde. Single crystal X-ray data was obtained for all thirteen compounds. In order to determine the effect of the different pendent –R groups, four properties were investigated: π–π distance, inward tilt, twist angle, and the angle between the planes containing the pendent –R groups. Positioning of the –R groups, the carbon atom chain length of the –R groups, the number of upper-rim hydroxyl groups (resorcin[4]arene vs. pyrogallol[4]arene), and the number of substituted phenyl groups all influenced these four properties. The trends that develop are investigated and discussed.
Co-reporter:Asanka S. Rathnayake, Kyle A. Feaster, Joshua White, Charles L. Barnes, Simon J. Teat, and Jerry L. Atwood
Crystal Growth & Design 2016 Volume 16(Issue 7) pp:3562-3564
Publication Date(Web):May 13, 2016
DOI:10.1021/acs.cgd.6b00306
The synthesis and X-ray crystallographic structure of the first cobalt-seamed hexameric nanocapsule, [Co24(C-pentylpyrogallol[4]arene)6], is presented. The overall metal–ligand arrangement of this novel capsule is similar to that of previously reported copper- and nickel-seamed hexameric nanocapsules. However, the title nanocapsule encloses a larger void space than those found in previous hexameric nanocapsules.
Co-reporter:Rahul S. Patil;Dr. Debasis Banerjee;Dr. Chen Zhang;Dr. Praveen K. Thallapally; Jerry L. Atwood
Angewandte Chemie International Edition 2016 Volume 55( Issue 14) pp:4523-4526
Publication Date(Web):
DOI:10.1002/anie.201600658
Abstract
Considering the rapidly rising CO2 level, there is a constant need for versatile materials which can selectively adsorb CO2 at low cost. The quest for efficient sorptive materials is still on since the practical applications of conventional porous materials possess certain limitations. In that context, we designed, synthesized, and characterized two novel supramolecular organic frameworks based on C-pentylpyrogallol[4]arene (PgC5) with spacer molecules, such as 4,4′-bipyridine (bpy). Highly optimized and symmetric intermolecular hydrogen-bonding interactions between the main building blocks and comparatively weak van der Waals interactions between solvent molecules and PgC5 leads to the formation of robust extended frameworks, which withstand solvent evacuation from the crystal lattice. The evacuated framework shows excellent affinity for carbon dioxide over nitrogen and adsorbs ca. 3 wt % of CO2 at ambient temperature and pressure.
Co-reporter:Rahul S. Patil;Dr. Debasis Banerjee;Dr. Chen Zhang;Dr. Praveen K. Thallapally; Jerry L. Atwood
Angewandte Chemie 2016 Volume 128( Issue 14) pp:4599-4602
Publication Date(Web):
DOI:10.1002/ange.201600658
Abstract
Considering the rapidly rising CO2 level, there is a constant need for versatile materials which can selectively adsorb CO2 at low cost. The quest for efficient sorptive materials is still on since the practical applications of conventional porous materials possess certain limitations. In that context, we designed, synthesized, and characterized two novel supramolecular organic frameworks based on C-pentylpyrogallol[4]arene (PgC5) with spacer molecules, such as 4,4′-bipyridine (bpy). Highly optimized and symmetric intermolecular hydrogen-bonding interactions between the main building blocks and comparatively weak van der Waals interactions between solvent molecules and PgC5 leads to the formation of robust extended frameworks, which withstand solvent evacuation from the crystal lattice. The evacuated framework shows excellent affinity for carbon dioxide over nitrogen and adsorbs ca. 3 wt % of CO2 at ambient temperature and pressure.
Co-reporter:Collin M. Mayhan
The Journal of Physical Chemistry C 2016 Volume 120(Issue 24) pp:13159-13168
Publication Date(Web):May 19, 2016
DOI:10.1021/acs.jpcc.6b04690
Metal–organic frameworks (MOFs) are a class of porous materials with a wide variety of applications, including molecular adsorption and separation. Recently, the first MOF based on the zinc-seamed pyrogallol[4]arene nanocapsule as a secondary building unit was reported. The zinc-seamed nanocapsules are linked together with 4,4′-bipyridine, which is a divergent ligand commonly used in the synthesis of MOFs. In an effort to identify other likely candidates for nanocapsular linking, electronic structure calculations were performed to determine energetic and geometric properties of (Zn(C2O2H3)2)1,2Y model complexes, which have been shown previously to reliably model the zinc coordination sphere found in the nanocapsules. Here, Y represents one of 17 divergent ligands with N, S, or O electron-donating atoms. MOFs were synthesized and characterized from two of the ligands suggested as most suitable for further experimental study.
Co-reporter:Rahul S. Patil, Harshita Kumari, Charles L. Barnes and Jerry L. Atwood
Chemical Communications 2015 vol. 51(Issue 12) pp:2304-2307
Publication Date(Web):19 Dec 2014
DOI:10.1039/C4CC08388A
Supramolecular organic frameworks (SOFs) based on pyrogallol[4]arene and 4,4′-bipyridine-type spacer molecules have been investigated. The hydrogen bonding pattern and molecular arrangement in the crystal structures are engineered through the cocrystallization approach. The length of the spacer molecules and the C-alkyl tail length of the PgC macrocycle are tuned to influence the hydrogen bonding pattern and thus the overall architecture of the resultant SOFs. Combined solid-state thermal analysis and solution-phase 1H NMR results indicate the amount of solvent loss and the stability of the SOFs in solution.
Co-reporter:Rahul S. Patil, Amanda M. Drachnik, Harshita Kumari, Charles L. Barnes, Carol A. Deakyne, and Jerry L. Atwood
Crystal Growth & Design 2015 Volume 15(Issue 6) pp:2781
Publication Date(Web):March 18, 2015
DOI:10.1021/acs.cgd.5b00148
Supramolecular organic frameworks based on C-alkylresorcin[4]arenes (RsCn) and the conformationally flexible spacer 1,2-bis(4-pyridyl)ethane (bpea) are discussed here. The conformational flexibility of bpea was predetermined with the help of electronic structure calculations of bpea in the gas and solution phases. The architectures of these frameworks are primarily governed by O–H···O and O–H···N intermolecular hydrogen-bonding interactions between the components of the frameworks. The unique arrangement of the bpea spacer around RsCn yields continuous 1D wavelike and 1D lateral hydrogen-bonded frameworks. The cocrystals of RsCn with bpea show conformational variation as a function of a change in the solvent of crystallization. In acetonitrile, the bpea spacer exists in the trans form, whereas in ethanol it adopts both gauche and trans forms. RsCn, on the other hand, adopts a pinched-cone conformation in both solvents. The extended frameworks of RsCn–bpea in ethanol enclose continuous channels filled with arrays of hydrogen-bonded gauche-bpea molecules.
Co-reporter:Constance R. Pfeiffer, Drew A. Fowler, and Jerry L. Atwood
Crystal Growth & Design 2015 Volume 15(Issue 8) pp:3992
Publication Date(Web):June 2, 2015
DOI:10.1021/acs.cgd.5b00609
Cocrystals composed of a pyrogallol[4]arene molecule (one of C-propylpyrogallol[4]arene in ethanol and one of C-hexylpyrogallol[4]arene in isopropanol) and a pyrene molecule were crystallized and investigated with the aim to develop trends based on solvent and aliphatic tail length of the pyrogallol[4]arene. These new trends along with previously determined trends for the fluorescent probe 1-(2-pyridylazo)-2-naphthol (PAN), were then used to crystallize a cocrystal composed of C-hexylpyrogallol[4]arene and two fluorescent probes, pyrene and PAN. Within a two-component cocrystal of pyrene or PAN, the probe molecules are complexed in both the endo (inside the pyrogallol[4]arene bowl) and exo (outside the pyrogallol[4]arene bowl) positions. However, in the three component system, selective complexation of the probes is demonstrated whereby the PAN molecules prefer to be endo and the pyrene molecules occupy exo positions.
Co-reporter:Constance R. Pfeiffer, Drew A. Fowler and Jerry L. Atwood
CrystEngComm 2015 vol. 17(Issue 24) pp:4475-4485
Publication Date(Web):19 May 2015
DOI:10.1039/C5CE00771B
Cocrystal systems containing pyrogallol[4]arene molecules of various aliphatic tail lengths, the fluorescent probe rhodamine B, and a variety of solvents are examined and discussed. Additionally, two pyronin Y cocrystals of C-methylpyrogallol[4]arene in methanol and C-ethylpyrogallol[4]arene in ethanol are crystallized and analyzed. For both the pyronin Y and rhodamine B cocrystals, solvent and aliphatic chain length have an effect on the packing, bowl shape of the pyrogallol[4]arene, probe complexation, and hydrogen bonding schemes. With pyronin Y cocrystals of C-methylpyrogallol[4]arene form a tube-like structure, with pyronin Y molecules in the centre of the tube while cocrystals of C-ethylpryogallol[4]arene form a bilayer-type structure.
Co-reporter:Jerry L. Atwood
Crystal Growth & Design 2015 Volume 15(Issue 6) pp:2874
Publication Date(Web):April 16, 2015
DOI:10.1021/acs.cgd.5b00317
The active pharmaceutical ingredient (API) may be physically separated from the excipients in a pharmaceutical formulation by making use of the difference in density of the API and that of the excipients. The API may then be fully characterized by standard techniques. In the density separation process, the API is not dissolved, and the crystal form of the API is not changed. As examples, Form I fexofenadine hydrochloride is separated from Allegra Allergy 24 h Tablets, and Form I lansoprazole is separated from Equate Lansoprazole Delayed Release Capsules.
Co-reporter:Constance R. Pfeiffer, Stuart G. Atwood, Luca Samadello, and Jerry L. Atwood
Crystal Growth & Design 2015 Volume 15(Issue 6) pp:2958
Publication Date(Web):April 23, 2015
DOI:10.1021/acs.cgd.5b00385
Cocrystals composed of various pyrogallol[4]arenes of different tail lengths with anthracene-based probes in a series of solvent systems are analyzed and compared with the aim to determine the effects of solvent, tail length, and functionality of the probe. The five main characteristics that are influenced are the bowl shape of the pyrogallol[4]arene, complexation of the probe molecule, the C–H···π interactions, the overall hydrogen bonding scheme, and the final ratio of probe to pyrogallol[4]arene. With modifications to the probe molecules, the characteristics most influenced are the bowl shape of the pyrogallol[4]arene, the C–H···π interactions, and the hydrogen bond schemes. Alterations in aliphatic tail length affect the complexation of the probe along with the C–H···π interactions and hydrogen bonding scheme. Solvent has an effect on the complexation of the probe, the final ratio of probe to pyrogallol[4]arene, the bowl shape of the pyrogallol[4]arene, and the hydrogen bonding schemes. Emerging trends due to these modifications are examined and discussed.
Co-reporter:Rahul S. Patil; Harshita Kumari;Dr. Charles L. Barnes; Jerry L. Atwood
Chemistry - A European Journal 2015 Volume 21( Issue 29) pp:10431-10435
Publication Date(Web):
DOI:10.1002/chem.201406574
Abstract
New oval-shaped capsular and bilayer-type hydrogen-bonded arrangements of C-propyl-ol-pyrogallol[4]arene (PgC3-OH) with bipyridine-type spacer complexes are reported here. These complexes are engineered by virtue of derivatization of C-alkyl tails of pyrogallol[4]arene and the use of divergent spacer ligands. Complexes of PgC3-OH, PgC3-OH with bpy (4,4′-bipyridine) and PgC3-OH with bpa (1,2-bis(4-pyridyl)acetylene) have bilayer type arrangements; however, the use of hydrogen chloride causes protonation of bpy molecule, which is then entrapped flat within an offset oval-shaped dimeric hydrogen-bonded PgC3-OH nanocapsule. The presence of chloride anion in the crystal lattice controls the geometry of the resultant nanoassembly.
Co-reporter:Harshita Kumari, Carol A. Deakyne, and Jerry L. Atwood
Accounts of Chemical Research 2014 Volume 47(Issue 10) pp:3080
Publication Date(Web):September 8, 2014
DOI:10.1021/ar500222w
Nanoassemblies of hydrogen-bonded and metal-seamed pyrogallol[4]arenes have been shown to possess novel solution-phase geometries. Further, we have demonstrated that both guest encapsulation and structural rearrangements may be studied by solution-phase techniques such as small-angle neutron scattering (SANS) and diffusion NMR. Application of these techniques to pyrogallol[4]arene-based nanoassemblies has allowed (1) differentiation among spherical, ellipsoidal, toroidal, and tubular structures in solution, (2) determination of factors that control the preferred geometrical shape and size of the nanoassemblies, and (3) detection of small variations in metric dimensions distinguishing similarly and differently shaped nanoassemblies in a given solution. Indeed, we have shown that the solution-phase structure of such nanoassemblies is often quite different from what one would predict based on solid-state studies, a result in disagreement with the frequently made assumption that these assemblies have similar structures in the two phases. We instead have predicted solid-state architectures from solution-phase structures by combining the solution-phase analysis with solid-state magnetic and elemental analyses.Specifically, the iron-seamed C-methylpyrogallol[4]arene nanoassembly was found to be tubular in solution and predicted to be tubular in the solid state, but it was found to undergo a rearrangement from a tubular to spherical geometry in solution as a function of base concentration. The absence of metal within a tubular framework affects its stability in both solution and the solid state; however, this instability is not necessarily characteristic of hydrogen-bonded capsular entities. Even metal seaming of the capsules does not guarantee similar solid-state and solution-phase architectures. The rugby ball-shaped gallium-seamed C-butylpyrogallol[4]arene hexamer becomes toroidal on dissolution, as does the spherically shaped gallium/zinc-seamed C-butylpyrogallol[4]arene hexamer. However, the arenes are arranged differently in the two toroids, a variation that accounts for the differences in their sizes and guest encapsulation. Guest encapsulation of biotemplates, such as insulin, has demonstrated the feasibility of synthesizing nanocapsules with a volume three times that of a hexamer. The solution-phase studies have also demonstrated that the self-assembly of dimers versus hexamers can be controlled by the choice of metal, solvent, and temperature. Controlling the size of the host, nature of the metal, and identity of the guest will allow construction of targeted host–guest assemblies having potential uses as drug delivery agents, nanoscale reaction vessels, and radioimaging/radiotherapy agents. Overall, the present series of solid- and solution-phase studies has begun to pave the way toward a more complete understanding of the properties and behavior of complex supramolecular nanoassemblies.
Co-reporter:Harshita Kumari ; Ping Jin ; Simon J. Teat ; Charles L. Barnes ; Scott J. Dalgarno
Journal of the American Chemical Society 2014 Volume 136(Issue 49) pp:17002-17005
Publication Date(Web):November 18, 2014
DOI:10.1021/ja5107354
Thallium ions are transported to the interior of gallium-seamed pyrogallol[4]arene nanocapsules. In comparison to the capture of Cs ions, the extent of which depends on the type and position of the anion employed in the cesium salt, the enhanced strength of Tl···π vs Cs···π interactions facilitates permanent entrapment of Tl+ ions on the capsule interior. “Stitching-up” the capsule seam with a tertiary metal (Zn, Rb, or K) affords new trimetallic nanocapsules in solid state.
Co-reporter:Andrew V. Mossine, Collin M. Mayhan, Drew A. Fowler, Simon J. Teat, Carol A. Deakyne and Jerry L. Atwood
Chemical Science 2014 vol. 5(Issue 6) pp:2297-2303
Publication Date(Web):19 Mar 2014
DOI:10.1039/C4SC00462K
The synthesis of a two-dimensional (2D) metal–organic framework (MOF) is described wherein Zn-seamed pyrogallol[4]arene (PgCx) nanocapsules are utilized as supramolecular building blocks with 4,4′-bipyridine (bpy) linkers. The choice of linker and of crystallization solvent (DMSO) was guided by electronic structure calculations on the zinc model complexes Zn(C2H3O2)2L, which showed that bpy and DMSO have similar Zn–L binding strengths and that there is little drop-off in binding strength when bpy is bound to a second Zn(C2H3O2)2 moiety. The MOF features unusual coordination geometries at the zinc centres along the nanocapsular periphery when compared to previous examples of zinc-seamed nanocapsules. The change in coordination geometry leads to a compulsory change in the internal volume of the nanocapsule as well as the behaviour of the encapsulated guest molecule. There are also several well defined voids and channels within the structure.
Co-reporter:Ping Jin, Harshita Kumari, Stuart Kennedy, Charles L. Barnes, Simon J. Teat, Scott J. Dalgarno and Jerry L. Atwood
Chemical Communications 2014 vol. 50(Issue 34) pp:4508-4510
Publication Date(Web):24 Mar 2014
DOI:10.1039/C4CC00202D
Addition of cadmium(II) nitrate to gallium-coordinated metal–organic C-alkylpyrogallol[4]arene nano-capsules affords a variation of the near spherical hexamer motif, structural changes in which are induced by the markedly different nature of the secondary incorporated metal.
Co-reporter:Harshita Kumari, Steven R. Kline, Drew A. Fowler, Andrew V. Mossine, Carol A. Deakyne and Jerry L. Atwood
Chemical Communications 2014 vol. 50(Issue 1) pp:109-111
Publication Date(Web):05 Nov 2013
DOI:10.1039/C3CC47029F
Giant nanocapsules: the solution-phase structures of PgC1Ho and PgC3Ho have been investigated using in situ neutron scattering measurements. The SANS results show the presence of spherical nanoassemblies of radius 18.2 Å, which are larger than the previously reported metal-seamed PgC3 hexamers (radius = 10 Å). The spherical architectures conform to a truncated cubeoctahedron geometry, indicating formation of the first metal-containing pyrogallol[4]arene-based dodecameric nanoassemblies in solution.
Co-reporter:Simon A. Herbert, Agnieszka Janiak, Praveen K. Thallapally, Jerry L. Atwood and Leonard J. Barbour
Chemical Communications 2014 vol. 50(Issue 98) pp:15509-15512
Publication Date(Web):07 Oct 2014
DOI:10.1039/C4CC07366E
The tetragonal apohost phase of p-tert-butyltetramethoxythiacalix[4]arene absorbs hydrochloric acid and iodine. These guest molecules occupy different sites in the solid-state structure – either within the small intrinsic voids of the macrocycle or within the interstitial spaces between the host molecules. This study illustrates the dynamic deformation of the host, providing strong mechanistic insight into the diffusion of guests into this seemingly non-porous material.
Co-reporter:Rahul S. Patil, Andrew V. Mossine, Harshita Kumari, Charles L. Barnes, and Jerry L. Atwood
Crystal Growth & Design 2014 Volume 14(Issue 10) pp:5212-5218
Publication Date(Web):August 19, 2014
DOI:10.1021/cg501014c
A family of hydrogen-bonded supramolecular frameworks based on C-alkylresorcinol[4]arene (RsC) and 4,4′-bipyridine (bpy) type spacers are described in this article. The size and shape of the void space enclosed within these frameworks are engineered by varying the type of solvent (acetonitrile and ethanol), spacer molecules (4,4′-bipyridine (bpy), trans-1,2-bis(4-pyridyl)ethylene (bpe), 1,2-bis(4-pyridyl)acetylene (bpa)), and the conformations and/or type of RsC bowl (boat vs cone or C-methylresorcin[4]arene/RsC1 vs C-propylresorcin[4]arene/RsC3). A change in the solvent system from acetonitrile to ethanol brings about a conformational change with the RsC1 macrocycle and also results in the distinct orientation of spacer molecules around the RsC macrocycle. The predominant feature in all of the frameworks is the O–H···N intermolecular interaction between RsC building blocks and bipyridine-type spacers. The resultant solvent-filled void spaces available within frameworks can be controlled by manipulating the parameters investigated in this study.
Co-reporter:Drew A. Fowler, Constance R. Pfeiffer, Simon J. Teat, Gary A. Baker, and Jerry L. Atwood
Crystal Growth & Design 2014 Volume 14(Issue 8) pp:4199-4204
Publication Date(Web):July 7, 2014
DOI:10.1021/cg500793z
The pyrogallol[4]arenes have been shown to act as versatile host macrocycles for a wide variety of guest molecules, including the imidazolium-based cations of ionic liquids. This report demonstrates the use of alkyl-linked geminal dications in the design of bilayers comprising dimeric host–guest complexes. The pivotal role of solvent choice in controlling the resultant solid-state structure is particularly highlighted. The synthesis and single-crystal X-ray diffraction structures of two dimeric host–guest cocrystals generated by the use of different solvents while employing identical host and guest species are presented to illustrate this point. In one solvent, a “Pac-man”-type dimeric host–guest complex is assembled into bilayer galleries. With a switch to an alternate crystallization solvent, a bilayer-type structure in which each layer is composed of alternating complexes of a capsule and two “offset dimers” is instead constructed.
Co-reporter:Harshita Kumari, Andrew V. Mossine, Nathaniel J. Schuster, Charles L. Barnes, Carol A. Deakyne and Jerry L. Atwood
CrystEngComm 2014 vol. 16(Issue 18) pp:3718-3721
Publication Date(Web):24 Mar 2014
DOI:10.1039/C3CE42412J
The syntheses and single-crystal XRD structures of copper-seamed C-alkylpyrogallol[4]arene (PgCnCu, n = 3, 7, 9) hexamers with different tail lengths are reported. Differences in the packing arrangements as a function of tail length are revealed. The progression in the size of the hexamers in the solid state is in agreement with that in the solution phase.
Co-reporter:Constance R. Pfeiffer, Drew A. Fowler, Simon Teat and Jerry L. Atwood
CrystEngComm 2014 vol. 16(Issue 47) pp:10760-10773
Publication Date(Web):23 Sep 2014
DOI:10.1039/C4CE01768D
Cocrystallizations of pyrogallol[4]arenes and 1-(2-pyridylazo)-2-naphthol (PAN) are investigated herein in order to determine the effect of aliphatic tail-length and solvent on crystal packing, probe orientation, and pyrogallol[4]arene bowl-shape. It is seen that solvent affects the final ratio of PAN to pyrogallol[4]arene, while aliphatic tail-length influences the crystal packing, C–H⋯π interactions, and overall hydrogen bonding. With an aliphatic tail-length of one carbon atom, there is an atypical bilayer structure. As the aliphatic tail-length increases, the resulting cocrystals have the characteristic bilayer structure as well as an increased number of C–H⋯π interactions and decreased hydrogen bonding with the PAN molecules.
Co-reporter:Amanda M. Drachnik, Harshita Kumari, Charles L. Barnes, Carol A. Deakyne and Jerry L. Atwood
CrystEngComm 2014 vol. 16(Issue 31) pp:7172-7175
Publication Date(Web):15 May 2014
DOI:10.1039/C4CE00556B
The syntheses and single-crystal X-ray structures of Mn- and Co-DMSO inclusion complexes with C-propylresorcin[4]arene dimers are reported. The Mn complex exists in one form (1), whereas the Co complex exists in two forms (2a and 2b). The hydrogen-bonded, head-to-head dimers of 1 and 2a are isostructural, with the macrocycles connected by tri-solvent bridges. The di-solvent bridged hydrogen bonds of 2b connect diagonal macrocycles.
Co-reporter:Constance R. Pfeiffer, Drew A. Fowler, and Jerry L. Atwood
Crystal Growth & Design 2014 Volume 14(Issue 8) pp:4205-4213
Publication Date(Web):July 15, 2014
DOI:10.1021/cg500794w
Cocrystal systems containing pyrogallol[4]arene, xanthone, and solvent molecules are examined and discussed. Three types of pyrogallol[4]arenes are cocrystallized with xanthone in isopropanol, acetonitrile, dimethyl sulfoxide, and a mixture of isopropanol and methanol. It is found that the solvent controls complexation of the xanthone molecule, whereas pyrogallol[4]arene tail length affects cocrystal packing. With a single-solvent system, the xanthone molecule is outside (exo) of the bowl of the pyrogallol[4]arene, but with a two-solvent system, the xanthone molecule is inside (endo) of the bowl of the pyrogallol[4]arene.
Co-reporter:Dr. Harshita Kumari;Dr. Ping Jin;Dr. Simon J. Teat;Dr. Charles L. Barnes;Dr. Scott J. Dalgarno; Jerry L. Atwood
Angewandte Chemie International Edition 2014 Volume 53( Issue 48) pp:13088-13092
Publication Date(Web):
DOI:10.1002/anie.201406776
Abstract
Anions play a crucial role in locking alkali metals on the interior of metal–organic capsules that contain structural water gates. This role is further evidenced when stitching-up the capsule seam, resulting in either expulsion or trapping of cesium ions depending on the anion employed.
Co-reporter:Dr. Harshita Kumari;Dr. Ping Jin;Dr. Simon J. Teat;Dr. Charles L. Barnes;Dr. Scott J. Dalgarno; Jerry L. Atwood
Angewandte Chemie 2014 Volume 126( Issue 48) pp:13304-13308
Publication Date(Web):
DOI:10.1002/ange.201406776
Abstract
Anions play a crucial role in locking alkali metals on the interior of metal–organic capsules that contain structural water gates. This role is further evidenced when stitching-up the capsule seam, resulting in either expulsion or trapping of cesium ions depending on the anion employed.
Co-reporter:Harshita Kumari ; Loredana Erra ; Alicia C. Webb ; Prashant Bhatt ; Charles L. Barnes ; Carol A. Deakyne ; John E. Adams ; Leonard J. Barbour
Journal of the American Chemical Society 2013 Volume 135(Issue 45) pp:16963-16967
Publication Date(Web):September 16, 2013
DOI:10.1021/ja406643b
Two forms of interdigitated layered arrangements of C-pentylpyrogallol[4]arene (PgC5) have been structurally elucidated and show variations in packing arrangements and host–guest interactions. Molecular dynamics simulations reveal a propensity for formation of self-included dimers, with or without incorporated solvent. Combined gas sorption and PXRD results show the presence of seven forms of PgC5, with and without CO2 (and their interconversions). This is the first CO2 gas sorption study of pyrogallol[4]arenes, and it provides evidence that pyrogallol[4]arenes may act as frustrated organic solids.
Co-reporter:Harshita Kumari ; Cindi L. Dennis ; Andrew V. Mossine ; Carol A. Deakyne
Journal of the American Chemical Society 2013 Volume 135(Issue 19) pp:7110-7113
Publication Date(Web):April 23, 2013
DOI:10.1021/ja402496x
The differences in magnetic properties of metal-based nanometric assemblies are due to distinct contributions from host–guest interactions, structural integrity, and magnetic interactions. To disentangle these contributions, it is necessary to control the self-assembly process that forms these entities. Herein we study the effect of host-to-guest ratios to identify remarkably different structural–magnetic contributions of C-methylpyrogallol[4]arene⊂ferrocene/(PgC1)2⊂Fc dimers vs (PgC1)3⊂Fc nanotubes. At low temperature, a weak anti-ferromagnetic alignment is observed, suggesting a weak dipolar interaction between Fc guest moieties within adjacent dimers or tubes. Also, differences are observed between magnetic atom occupancy as a function of guest (PgC1⊂Fc tube/dimer) versus magnetic atom occupancy within the framework wall (PgC3Ni hexamer/dimer). Identification of the role of the framework shape and metal–metal distances in the crystal lattice opens up unparalleled prospects for materials engineering.
Co-reporter:Drew A. Fowler ; Asanka S. Rathnayake ; Stuart Kennedy ; Harshita Kumari ; Christine M. Beavers ; Simon J. Teat
Journal of the American Chemical Society 2013 Volume 135(Issue 33) pp:12184-12187
Publication Date(Web):August 2, 2013
DOI:10.1021/ja404392m
The synthesis and single-crystal X-ray diffraction structure of a dimeric zinc-seamed nanocapsule using a mixed pyrogallol/resorcinol[4]arene are presented. The use of “mixed” macrocycles results in an incomplete seam of coordination bonds around the nanocapsule’s typically octa-metalated belt. The self-assembly of the nanocapsule occurs such that the single resorcinol moiety of each macrocycle aligns transversely. This yields a hepta-metalated capsule where the defect occurs in such a way as to provide minimal disruption to the overall structure of the nanocapsule.
Co-reporter:Andrew V. Mossine, Praput Thavornyutikarn and Jerry L. Atwood
CrystEngComm 2013 vol. 15(Issue 9) pp:1673-1675
Publication Date(Web):18 Dec 2012
DOI:10.1039/C2CE26802G
The structures of a macrocyclic C-hexyltetracyanoresorcin[4]arene (RsCNC6) methanol solvate and a corresponding metal–organic framework consisting of 1:1 RsCNC6:Ag+ are reported. Solvent-filled channels are apparent in both structures. A conserved stacking motif that involves the upper rim cyano groups and the pendant C-hexyl chains of the resorcinarene is also described.
Co-reporter:Harshita Kumari, Jin Zhang, Loredana Erra, Leonard J. Barbour, Carol A. Deakyne and Jerry L. Atwood
CrystEngComm 2013 vol. 15(Issue 20) pp:4045-4048
Publication Date(Web):08 Apr 2013
DOI:10.1039/C3CE40441B
The synthesis of cocrystals of gabapentin (GBP) with resorcin[4]arenes (RsCn) with different tail lengths, C-hexylresorcin[4]arene (RsC6) and C-propylresorcin[4]arene (RsC3), is reported. The structural elucidations of the two cocrystals show differences in packing arrangements and host–guest interactions.
Co-reporter:Harshita Kumari, Steven R. Kline and Jerry L. Atwood
Chemical Communications 2012 vol. 48(Issue 30) pp:3599-3601
Publication Date(Web):14 Feb 2012
DOI:10.1039/C2CC18071E
Solution structure of insulin templated C-methyl resorcin[4]arene nanocapsules has been investigated using neutron scattering. The insulin biotemplate has enhanced the limits of encapsulation and enabled formation of a larger spherical molecular host.
Co-reporter:Drew A. Fowler, Simon J. Teat, Gary A. Baker and Jerry L. Atwood
Chemical Communications 2012 vol. 48(Issue 43) pp:5262-5264
Publication Date(Web):30 Mar 2012
DOI:10.1039/C2CC31510F
We report on a cocrystal between C-propyl pyrogallol[4]arene and the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate exhibiting a remarkable bilayer topology comprising two unique host–guest complexes resulting from the ionic liquid cation binding in two distinctive orientations relative to the macrocycle.
Co-reporter:Dr. Harshita Kumari;Dr. Steven R. Kline;Dr. Cindi L. Dennis;Andrew V. Mossine;Dr. Rick L. Paul; Carol A. Deakyne; Jerry L. Atwood
Angewandte Chemie International Edition 2012 Volume 51( Issue 37) pp:
Publication Date(Web):
DOI:10.1002/anie.201206327
Co-reporter:Dr. Harshita Kumari;Andrew V. Mossine;Dr. Steven R. Kline;Dr. Cindi L. Dennis;Dr. Drew A. Fowler;Dr. Simon J. Teat;Dr. Charles L. Barnes; Carol A. Deakyne; Jerry L. Atwood
Angewandte Chemie International Edition 2012 Volume 51( Issue 6) pp:1452-1454
Publication Date(Web):
DOI:10.1002/anie.201107182
Co-reporter:Andrew V. Mossine;Dr. Harshita Kumari;Dr. Drew A. Fowler;Annie Shih;Dr. Steven R. Kline;Dr. Charles L. Barnes; Jerry L. Atwood
Chemistry - A European Journal 2012 Volume 18( Issue 33) pp:10258-10260
Publication Date(Web):
DOI:10.1002/chem.201200263
Co-reporter:Dr. Harshita Kumari;Dr. Steven R. Kline;Dr. Wei G. Wycoff;Dr. Rick L. Paul;Andrew V. Mossine; Carol A. Deakyne; Jerry L. Atwood
Angewandte Chemie International Edition 2012 Volume 51( Issue 21) pp:5086-5091
Publication Date(Web):
DOI:10.1002/anie.201200209
Co-reporter:Dr. Harshita Kumari;Dr. Steven R. Kline;Dr. Cindi L. Dennis;Andrew V. Mossine;Dr. Rick L. Paul; Carol A. Deakyne; Jerry L. Atwood
Angewandte Chemie International Edition 2012 Volume 51( Issue 37) pp:9263-9266
Publication Date(Web):
DOI:10.1002/anie.201204776
Co-reporter:Harshita Kumari, Cindi L. Dennis, Andrew V. Mossine, Carol A. Deakyne, and Jerry L. Atwood
ACS Nano 2012 Volume 6(Issue 1) pp:272
Publication Date(Web):December 9, 2011
DOI:10.1021/nn203540e
The magnetic behavior of nickel-seamed C-propylpyrogallol[4]arene dimeric and hexameric nanocapsular assemblies has been investigated in the solid state using a SQUID magnetometer. These dimeric and hexameric capsular entities show magnetic differentiation both in terms of moment per nanocapsule and potential antiferromagnetic interactions within individual nanocapsules. The weak antiferromagnetic behavior observed at low temperatures indicates dipolar interactions between neighboring nickel atoms; however, this effect is higher in the hexameric nickel-seamed assembly. The differences in magnetic behavior of dimer versus hexamer can be attributed to different coordination environments and metal arrangements in the two nanocapsular assemblies.Keywords: dimeric nickel-seamed nanocapsule; hexameric nickel-seamed nanocapsule; pyrogallol; soild-state magnetic behavior
Co-reporter:Jian Tian ; Scott J. Dalgarno
Journal of the American Chemical Society 2011 Volume 133(Issue 5) pp:1399-1404
Publication Date(Web):January 5, 2011
DOI:10.1021/ja107617m
The robust nature of network materials allows them to (for example) respond to external stimuli such as pressure, temperature, light, or gas/solvent adsorption and desorption. There is difficulty in retaining long-range order in purely molecular organic solids, due to weak intermolecular interactions such as van der Waals forces. Here, we show gas-induced transformations of the well-known pharmaceuticals clarithromycin and lansoprazole. For clarithromycin, the stimulus is capable of converting the kinetic solvate and guest-free crystal forms to the commercial thermodynamically stable polymorph with a huge saving in energy cost relative to industrially employed methods. The synthesis of the marketing form of lansoprazole involves a solvate that readily decomposes and that is stirred in water, filtered, and dried intensively. Our method readily circumvents such synthetic problems and transforms the sensitive solvate to the marketed drug substance with ease. Such expedient transformations hold great implications for the pharmaceutical industry in general when considering the ease of transformation and mild conditions employed.
Co-reporter:Drew A. Fowler ; Andrew V. Mossine ; Christine M. Beavers ; Simon J. Teat ; Scott J. Dalgarno
Journal of the American Chemical Society 2011 Volume 133(Issue 29) pp:11069-11071
Publication Date(Web):June 21, 2011
DOI:10.1021/ja203651v
Copper seamed dimeric metal–organic pyrogallol[4]arene capsules have been synthesized and engineered into coordination polymer chains, either by direct coordination or with additional bridging ligands. The formation of this copper capsule also demonstrates selective formation of either hexameric or dimeric metal–organic capsules.
Co-reporter:Harshita Kumari ; Steven R. Kline ; Nathaniel J. Schuster ; Charles L. Barnes
Journal of the American Chemical Society 2011 Volume 133(Issue 45) pp:18102-18105
Publication Date(Web):October 4, 2011
DOI:10.1021/ja208195t
Small-angle neutron scattering (SANS) studies were used to probe the stability and geometry of copper-seamed C-alkylpyrogallol[4]arene (PgCnCu; n = 11, 13, 17) hexamers in solution. Novel structural features are observed at chain lengths greater than 10 in both solid and solution phase. Scattering data for the PgC11Cu and PgC13Cu in chloroform fitted as core–shell spheres with a total spherical radius of about 22.7 and 22.9 Å respectively. On the other hand, the scattering curve for the PgC17Cu hexamer at both 1% and 5% mass fractions in o-xylene did not fit as a discrete sphere but rather as a uniform ellipsoid. The geometric dimensions of the ellipsoid radii are 24 Å along the minor axis and 115 Å along the major axis. It is expected that an individual hexamer with heptadecyl chains would exhibit a uniform radius of ca. 24 Å. However, an approximate ratio of 1:5 between radii lengths for the minor axis and major axis is consistent with interpenetration of the heptadceyl chains of adjacent hexamers to form a single ellipsoidal assembly.
Co-reporter:Jian Tian, Shengqian Ma, Praveen K. Thallapally, Drew Fowler, B Peter McGrail and Jerry L. Atwood
Chemical Communications 2011 vol. 47(Issue 27) pp:7626-7628
Publication Date(Web):10 Jun 2011
DOI:10.1039/C1CC12689J
Cucurbit[7]uril (CB[7]), in its amorphous solid state, shows one of the highest CO2 sorption capacities among known organic porous materials at 298 K and 0.1 and 1 bar. In addition to the highest CO2 capacity, CB[7] also shows remarkable selectivity of CO2 over N2 and CH4. These properties, along with the existence of readily available precursors, indicate amorphous CB[7] might find applications in recycling CO2 particularly considering the easy synthesis and potentially low manufacturing costs.
Co-reporter:Harshita Kumari, Steven R. Kline, Nathaniel J. Schuster and Jerry L. Atwood
Chemical Communications 2011 vol. 47(Issue 45) pp:12298-12300
Publication Date(Web):25 Oct 2011
DOI:10.1039/C1CC15615B
The stability of copper-seamed C-alkylpyrogallol[4]arene hexamers with varying chain lengths in solution has been studied using small-angle neutron scattering (SANS). The progression in diameter of spherical capsules with increasing alkyl chain lengths of copper-seamed hexamers in solution suggests both robustness as well as a close correlation between the solid phase and solution phase structures.
Co-reporter:Jian Tian, Praveen Thallapally, Jun Liu, Gregory J. Exarhos and Jerry L. Atwood
Chemical Communications 2011 vol. 47(Issue 2) pp:701-703
Publication Date(Web):16 Nov 2010
DOI:10.1039/C0CC04260A
A well-known organic host, tris-o-phenylenedioxycyclotriphosphazene, exists in two polymorphic guest-free forms: the thermodynamic nonporous high-density phase and the kinetic nanoporous low-density phase. Simple pressurization of the high density phase with CO2 brings a solid-state transformation to the low density phase, resulting in significant expansion of the crystal volume by 23%.
Co-reporter:Drew A. Fowler, Jian Tian, Charles Barnes, Simon J. Teat and Jerry L. Atwood
CrystEngComm 2011 vol. 13(Issue 5) pp:1446-1449
Publication Date(Web):17 Nov 2010
DOI:10.1039/C0CE00661K
The single crystal X-ray diffraction structures for three cocrystals of C-butyl pyrogallol[4]arene and C-propan-3-ol pyrogallol[4]arene with the pharmaceutical gabapentin are described. The variation of solvent conditions and functionalities of the pyrogallol[4]arene tails demonstrates how these calixarene-like molecules can be used in the design of cocrystals with target molecules.
Co-reporter:Andrew V. Mossine;Harshita Kumari;Drew A. Fowler;Andrew K. Maerz;Steven R. Kline;Charles L. Barnes
Israel Journal of Chemistry 2011 Volume 51( Issue 7) pp:840-842
Publication Date(Web):
DOI:10.1002/ijch.201100068
No abstract is available for this article.
Co-reporter:Dr. Katrina K. Kline;Drew A. Fowler;Dr. Sheryl A. Tucker ;Dr. Jerry L. Atwood
Chemistry - A European Journal 2011 Volume 17( Issue 39) pp:10848-10851
Publication Date(Web):
DOI:10.1002/chem.201101297
Co-reporter:Ping Jin, Scott J. Dalgarno, Jerry L. Atwood
Coordination Chemistry Reviews 2010 Volume 254(15–16) pp:1760-1768
Publication Date(Web):August 2010
DOI:10.1016/j.ccr.2010.04.009
The formation of hydrogen-bonded nanometer scale capsules from C-methylresorcin[4]arene represented a new area of research within the broad field of supramolecular chemistry. The related pyrogallol[4]arenes form nanocapsules of similar dimensions and this research now extends into the formation of novel metal-organic nanocapsules (MONCs). These relatively new systems are described here, with particular focus on recent advances in the formation of MONCs that are seamed together by more than one type of metal ion. This chemistry holds great potential for the isolation of designer materials that allow for enhanced control over the ratios of metal ions within these supramolecular assemblies.
Co-reporter:Andrew K. Maerz, Haunani M. Thomas, Nicholas P. Power, Carol A. Deakyne and Jerry L. Atwood
Chemical Communications 2010 vol. 46(Issue 8) pp:1235-1237
Publication Date(Web):15 Jan 2010
DOI:10.1039/B921911K
An induced cis–trans–trans (rctt) chair to cone structural rearrangement is forced by the addition of a pentacoordinate zinc(II) complex, overcoming thermodynamic and kinetic factors to produce the first phenyl-substituted zinc dimeric nanocapsule.
Co-reporter:Jerry L. Atwood, Euan K. Brechin, Scott J. Dalgarno, Ross Inglis, Leigh F. Jones, Andrew Mossine, Martin J. Paterson, Nicholas P. Power and Simon J. Teat
Chemical Communications 2010 vol. 46(Issue 20) pp:3484-3486
Publication Date(Web):31 Mar 2010
DOI:10.1039/C002247K
Nickel and cobalt seamed metal–organic capsules have been isolated and studied using structural, magnetic and computational approaches. Antiferromagnetic exchange in the Ni capsule results from coordination environments enforced by the capsule framework.
Co-reporter:Jena L. Whetstine, Katrina K. Kline, Drew A. Fowler, Cheryl M. Ragan, Charles L. Barnes, Jerry L. Atwood and Sheryl A. Tucker
New Journal of Chemistry 2010 vol. 34(Issue 11) pp:2587-2591
Publication Date(Web):18 Aug 2010
DOI:10.1039/C0NJ00398K
Pyrogallol[4]arenes self-assemble to form stable hydrogen-bonded nanocapsules that have many unique properties making them potentially suitable for diverse applications, such as molecular transporters and nanoreactors. However, little is known about the host–guest behaviour of these materials. Utilizing nanoenvironment-dependent properties of the fluorescent reporter molecule, pyrene butanol (PBOH), the encapsulating abilities of the hexameric C-hexylpyrogallol[4]arene (PgC6) nanocages are further explored. Solution-state, spectroscopic and spectrofluorometric investigations and solid-state, single-crystal X-ray diffraction studies are in agreement and indicate an ordered inner phase. Up to two PBOH guest molecules are sequestered within the nanocapsule along with encapsulation solvent. The nature of the PBOH–PgC6 complex is found to change with time, as indicated by fluorophore leaching. These research findings provide additional insight into the encapsulation capabilities of PgCn nanocapsules.
Co-reporter:Jian Tian ; Praveen K. Thallapally ; Scott J. Dalgarno
Journal of the American Chemical Society 2009 Volume 131(Issue 37) pp:13216-13217
Publication Date(Web):August 28, 2009
DOI:10.1021/ja904658p
Clarithromycin is a well-known antibiotic that exists in various polymorphic forms. This molecule can be sublimed to afford a guest-free form that displays the unexpected transport of molecules of water or carbon dioxide to voids within the channel-free crystal lattice.
Co-reporter:Ping Jin, Scott J. Dalgarno, John E. Warren, Simon J. Teat and Jerry L. Atwood
Chemical Communications 2009 (Issue 23) pp:3348-3350
Publication Date(Web):19 May 2009
DOI:10.1039/B822430G
The stepwise synthesis of mixed metal–organic C-alkylpyrogallol[4]arene nanocapsules allows control over the metal ratios in the resulting assembliesvia sequential incorporation and ejection of different metals.
Co-reporter:Scott J. Dalgarno, Tamas Szabo, Ali Siavosh-Haghighi, Carol A. Deakyne, John E. Adams and Jerry L. Atwood
Chemical Communications 2009 (Issue 11) pp:1339-1341
Publication Date(Web):09 Jan 2009
DOI:10.1039/B819276F
Large fluorescent molecules have been encapsulated in pyrogallol[4]arene nano-capsules, thus exploring the limits of molecular encapsulation; the orientation of these probe molecules within these nano-capsules has been examined with additional computational approaches in one case.
Co-reporter:Jian Tian, Scott J. Dalgarno, Praveen K. Thallapally and Jerry L. Atwood
CrystEngComm 2009 vol. 11(Issue 1) pp:33-35
Publication Date(Web):15 Oct 2008
DOI:10.1039/B813628A
Parital de-solvation of the toluene solvate of p-tert-butylcalix[5]arene affords a frustrated organic solid that is a new type of sorbant. Increased control over this sorption is achieved by employing a high boiling solvent for incremental de-solvation, revealing the calixarene:solvent ratio for maximum gas sorption.
Co-reporter:Jian Tian;PraveenK. Thallapally Dr.;ScottJ. Dalgarno Dr.;PeterB. McGrail Dr.;JerryL. Atwood
Angewandte Chemie 2009 Volume 121( Issue 30) pp:5600-5603
Publication Date(Web):
DOI:10.1002/ange.200900479
Co-reporter:Jian Tian;PraveenK. Thallapally Dr.;ScottJ. Dalgarno Dr.;PeterB. McGrail Dr.;JerryL. Atwood
Angewandte Chemie International Edition 2009 Volume 48( Issue 30) pp:5492-5495
Publication Date(Web):
DOI:10.1002/anie.200900479
Co-reporter:Scott J. Dalgarno, Nicholas P. Power, Jerry L. Atwood
Coordination Chemistry Reviews 2008 Volume 252(8–9) pp:825-841
Publication Date(Web):April 2008
DOI:10.1016/j.ccr.2007.10.010
The formation of capsule based architectures on the molecular scale has been of interest to many researchers in recent times. The formation of these assemblies is often challenging and can produce structures on a multi nano-metre scale that can serve specific functions. Some of the approaches used to produce such assemblies are outlined in relation to various building blocks in metal-organic polyhedra, molecular boxes and molecular capsules for example. The last of these has been the focus of our recent studies since the discovery of a hydrogen-bonded nano-capsule based on C-methylresorcin[4]arene, although the molecule also assembles in dimeric capsule motifs. The related pyrogallol[4]arenes display similar behaviour, however a number of metal-organic analogues have recently been synthesised and characterised through a variety of techniques that suggest various assembly processes. These are highlighted in the context of related architectures in order to give a sense of potential for such assemblies that can, in some cases, be assembled instantaneously or very rapidly.
Co-reporter:Scott J. Dalgarno, Nicholas P. Power, John E. Warren and Jerry L. Atwood
Chemical Communications 2008 (Issue 13) pp:1539-1541
Publication Date(Web):27 Feb 2008
DOI:10.1039/B719769A
Metal–organic pyrogallol[4]arene nano-capsules, mixed pyrogallol[4]arene nano-capsules, and mixed metal analogues have been rapidly synthesised by addition of excess copper nitrate to a methanol solution of the corresponding macrocycle(s) (or gallium nano-capsules for the mixed metal system); improved solubility allows for thorough study and elucidation of the assembly process for these discrete metal–organic assemblies.
Co-reporter:Scott J. Dalgarno, Karla M. Claudio-Bosque, John E. Warren, Timothy E. Glass and Jerry L. Atwood
Chemical Communications 2008 (Issue 12) pp:1410-1412
Publication Date(Web):19 Feb 2008
DOI:10.1039/B716777F
Reaction of p-carboxylatocalix[4]arene-O-methyl ether with either rubidium or caesium hydroxide results in the formation of interpenetrated nano-capsule networks with the calixarene in the 1,3-alternate conformation.
Co-reporter:Scott J. Dalgarno, Praveen K. Thallapally, Jian Tian and Jerry L. Atwood
New Journal of Chemistry 2008 vol. 32(Issue 12) pp:2095-2099
Publication Date(Web):17 Oct 2008
DOI:10.1039/B809457H
Crystallisation of the host molecule p-tert-butylcalix[5]arene from toluene affords three pseudo-polymorphs, two of which can be isolated on a large scale and used to form ‘frustrated’ organic solids that are capable of gas sorption. The structures of these three polymorphs are compared, and the gas sorption capabilities of the two phases that can be isolated in bulk form are described.
Co-reporter:Scott J. Dalgarno, Praveen K. Thallapally, Leonard J. Barbour and Jerry L. Atwood
Chemical Society Reviews 2007 vol. 36(Issue 2) pp:236-245
Publication Date(Web):02 Jan 2007
DOI:10.1039/B606047C
Seemingly non-porous organic solids have the ability for guest transport and have also been shown to absorb gases, including hydrogen, methane and acetylene, to varied extents. These materials also show potential for gas separation technology, display remarkable water transport through hydrophobic crystals, and clearly show that molecules within crystals are capable of cooperating with guests as they move through non-porous environments. This work is presented within a broader topic which also encompasses crystal engineering and (microporous) metal-organic frameworks (MOF's).
Co-reporter:Scott J. Dalgarno, Jian Tian, John E. Warren, Thomas E. Clark, Mohamed Makha, Colin L. Raston and Jerry L. Atwood
Chemical Communications 2007 (Issue 46) pp:4848-4850
Publication Date(Web):05 Oct 2007
DOI:10.1039/B712621B
Varied temperature sublimation of calix[5]arene results in the formation of two distinctly different crystal structures or polymorphs α and β, the latter of which is based on both ‘self-included’ and ‘back-to-back’ helical arrangements of the molecule, while also being active towards CO2 sorption at room temperature and 1 atmosphere pressure.
Co-reporter:Praveen K. Thallapally, B. Peter McGrail and Jerry L. Atwood
Chemical Communications 2007 (Issue 15) pp:1521-1523
Publication Date(Web):05 Feb 2007
DOI:10.1039/B617340C
The uptake of various nitrogen oxides was studied with the well known nonporous p-tert-butylcalix[4]arene under ambient conditions.
Co-reporter:Robert M. McKinlay, Scott J. Dalgarno, Peter J. Nichols, Stavroula Papadopoulos, Jerry L. Atwood and Colin L. Raston
Chemical Communications 2007 (Issue 23) pp:2393-2395
Publication Date(Web):15 Mar 2007
DOI:10.1039/B700984D
Hydrolysis of ‘tris(aryl or alkyl)gallium(III)’ species results in the formation of spheroidal dodecameric galloxane mixed oxide–hydroxide clusters, and shows that the gallium centres and associated residual alkyl/aryl groups are arranged at the polyhedral vertices of pseudo-icosahedra.
Co-reporter:Scott J. Dalgarno, Nicholas P. Power and Jerry L. Atwood
Chemical Communications 2007 (Issue 33) pp:3447-3449
Publication Date(Web):26 Jul 2007
DOI:10.1039/B707009H
Ionic capsules based on dimeric arrangements of pyrogallol[4]arenes have been structurally authenticated and suggest that there is a degree of flexibility in capsule formation with further potential for multiple guest encapsulation and manipulation in such arrangements.
Co-reporter:Praveen K. Thallapally, Karen A. Kirby and Jerry L. Atwood
New Journal of Chemistry 2007 vol. 31(Issue 5) pp:628-630
Publication Date(Web):20 Oct 2006
DOI:10.1039/B610321A
Sublimed, low-density p-tert-butylcalix[4]arene absorbs methane more readily at room temperature and 1 atm pressure than do either single wall carbon nanotubes (SWNT) or a comparative porous metal–organic framework (MOF-1).
Co-reporter:Scott J. Dalgarno, John E. Warren, Jochen Antesberger, Timothy E. Glass and Jerry L. Atwood
New Journal of Chemistry 2007 vol. 31(Issue 11) pp:1891-1894
Publication Date(Web):05 Oct 2007
DOI:10.1039/B712800B
Non-covalent nanotubular assemblies with large core diameters are rare. Here we show that simple crystallisation of para-carboxylatocalix[4]arene from pyridine results in the formation of one such assembly, facilitated by back-to-back packing of calixarenes and the well known pyridine–carboxylic acid interaction.
Co-reporter:Nicholas P. Power, Scott J. Dalgarno and Jerry L. Atwood
New Journal of Chemistry 2007 vol. 31(Issue 1) pp:17-20
Publication Date(Web):06 Dec 2006
DOI:10.1039/B615947H
The first metal coordinated pyrogallol[4]arene encapsulating dimer has been synthesised and shows high nuclearity with respect to ZnII, arranged as a polar coordination belt.
Co-reporter:Robert M. McKinlay Dr.;Jerry L. Atwood
Angewandte Chemie 2007 Volume 119(Issue 14) pp:
Publication Date(Web):21 FEB 2007
DOI:10.1002/ange.200604453
Mmm, Donuts! Sechs Calix[4]arenmoleküle bilden mithilfe von Wasserstoffbrücken eine große, hexamere, ringförmige Struktur (siehe Bild; Br gelb, O rot, C grau, H weiß). Das Donut-Gebilde hat im festen Zustand eine bemerkenswerte strukturelle Ähnlichkeit mit Cucurbit[6]uril und kann deshalb als ein nichtkovalentes Analogon gesehen werden.
Co-reporter:Scott J. Dalgarno Dr.;Jochen Antesberger;Robert M. McKinlay Dr.;Jerry L. Atwood
Chemistry - A European Journal 2007 Volume 13(Issue 29) pp:
Publication Date(Web):16 JUL 2007
DOI:10.1002/chem.200700441
Under various conditions, water molecules dramatically affect a number of solid-state C-alkylpyrogallol[4]arene assemblies. In the absence of water, hydrogen-bonded hexameric capsules are formed for the C-butyl, pentyl, hexyl, and heptyl pyrogallol[4]arenes. Introduction of water to acetonitrile solutions containing C-propyl–C-octylpyrogallol[4]arenes resulted in the formation of markedly different bilayer structures and the structural identification of two new dimer-type motifs.
Co-reporter:Nicholas P. Power Dr.;Scott J. Dalgarno Dr.;Jerry L. Atwood
Angewandte Chemie 2007 Volume 119(Issue 45) pp:
Publication Date(Web):20 SEP 2007
DOI:10.1002/ange.200702941
Nicht nur drinnen: Ein beliebig gewählter Gast, der in eine achtkernige Zink-gesäumte molekulare Pyrogallol[4]aren-Kapsel eingeschlossen ist, kann über Ligandenaustausch als Reporter für die elektronische Kommunikation zwischen dem Äußeren und dem Inneren der Kapsel fungieren.
Co-reporter:Nicholas P. Power Dr.;Scott J. Dalgarno Dr.;Jerry L. Atwood
Angewandte Chemie 2007 Volume 119(Issue 45) pp:
Publication Date(Web):8 NOV 2007
DOI:10.1002/ange.200790228
Ein einfühlsamer Gast in einer über acht Zinkionen verknüpften Pyrogallol[4]aren-Kapsel (Zn hellgrün, O rot, C schwarz) gibt Auskunft über die elektronische Kommunikation zwischen dem Kapselinneren und der Umgebung. J. L. Atwood und Mitarbeiter beschreiben in ihrer Zuschrift auf S. 8755 ff., wie der Austausch von Liganden (dargestellt als blaue und dunkelgrüne Kugeln) mit unterschiedlicher Elektronendonorwirkung zu den Metallzentren eine C-H⋅⋅⋅π-Wechselwirkung zwischen der Gastspezies und der Kapsel verstärken oder schwächen kann (verbildlicht durch verschiedene Farben der Gastspezies).
Co-reporter:Robert M. McKinlay Dr.;Jerry L. Atwood
Angewandte Chemie International Edition 2007 Volume 46(Issue 14) pp:
Publication Date(Web):21 FEB 2007
DOI:10.1002/anie.200604453
Mmm, doughnuts! Six calix[4]arene molecules self-assemble into a large hexameric torus-shaped structure through hydrogen bonds (see picture; Br yellow, O red, C gray, H white). The doughnut assembly shows a noteworthy structural similarity to cucurbit[6]uril in the solid state and therefore may be viewed as a noncovalent analogue.
Co-reporter:Nicholas P. Power Dr.;Scott J. Dalgarno Dr.;Jerry L. Atwood
Angewandte Chemie International Edition 2007 Volume 46(Issue 45) pp:
Publication Date(Web):20 SEP 2007
DOI:10.1002/anie.200702941
Not just an inside job: Encapsulated and confined in an octanuclear zinc-seamed pyrogallol[4]arene molecular capsule, a guest of choice can act as a reporter for electronic communication between the exterior and the interior of the capsule through ligand exchange (see structure of capsule, Zn light blue, O red, S yellow).
Co-reporter:Nicholas P. Power Dr.;Scott J. Dalgarno Dr.;Jerry L. Atwood
Angewandte Chemie International Edition 2007 Volume 46(Issue 45) pp:
Publication Date(Web):8 NOV 2007
DOI:10.1002/anie.200790228
A guest of choice confined within an octanuclear zinc-seamed pyrogallol[4]arene capsule (light green Zn, red O, black C) can act as a reporter for electronic communication between the exterior and interior of the capsule. As Atwood and co-workers report in their Communication on page 8601 ff., by interchanging ligands (represented by blue and dark green balls) and concomitantly varying electron donation to the metal centers, a CH⋅⋅⋅π interaction between the guest and the capsule is either enhanced or diminished (represented by the color of the guest).
Co-reporter:Robert M. McKinlay, Praveen K. Thallapally and Jerry L. Atwood
Chemical Communications 2006 (Issue 28) pp:2956-2958
Publication Date(Web):13 Jun 2006
DOI:10.1039/B605204E
Large multicomponent nanospheroid arrays consisting of six C-pentylpyrogallol[4]arene molecules and 12 Ga3+ metal-ions which in turn enclose 1150 Å3 of chemical space are reported.
Co-reporter:Scott J. Dalgarno, Nicholas P. Power, Jochen Antesberger, Robert M. McKinlay and Jerry L. Atwood
Chemical Communications 2006 (Issue 36) pp:3803-3805
Publication Date(Web):08 Aug 2006
DOI:10.1039/B605147B
Two lower rim halogenated pyrogallol[4]arenes have been synthesised and structurally characterised as either bi-layer or hexameric nano-capsule motifs depending upon chain length and functionalisation.
Co-reporter:Scott J. Dalgarno Dr.;Daniel B. Bassil;Sheryl A. Tucker Dr.
Angewandte Chemie 2006 Volume 118(Issue 42) pp:
Publication Date(Web):2 OCT 2006
DOI:10.1002/ange.200601961
Einschluss beleuchtet: Die molekulare Fluoreszenzsonde 4-[3-(9-Anthryl)propyl]-N,N-dimethylanilin (C grau, N blau) kristallisiert entweder in exo- oder in endo-Stellung bezüglich des Hohlraums von Pyrogallol[4]aren-Hexameren (O rot), was sich in deutlich verschiedenen Fluoreszenzemissionen äußert. In der exo-Anordnung verändern die Gastmoleküle die Packung des Hexamers, indem sie Kanäle in der aufgeweiteten Festkörperstruktur bilden (siehe Bild).
Co-reporter:Scott J. Dalgarno Dr.;Gareth W. V. Cave Dr.
Angewandte Chemie 2006 Volume 118(Issue 4) pp:
Publication Date(Web):27 DEC 2005
DOI:10.1002/ange.200503035
Der ultimative Strohhalm: Das Beschallen von C-Hexylpyrogallol[4]aren in Gegenwart von Pyren, Acetonitril und Wasser liefert kristalline organische Nanoröhren. In den aus den Calixarenen gebildeten Röhren mit großem Durchmesser liegen abwechselnd Acetonitril- und Wassermolekülpäckchen vor (siehe Bild; die Röhren- und Solvensmoleküle sind in Stab- bzw. Kalottendarstellung gezeigt).
Co-reporter:Praveen K. Thallapally Dr.;Liliana Dobrzańska Dr.;Todd R. Gingrich;Trevor B. Wirsig;Leonard J. Barbour
Angewandte Chemie 2006 Volume 118(Issue 39) pp:
Publication Date(Web):5 SEP 2006
DOI:10.1002/ange.200601391
Unübliche Speicherung: Ein organisches nichtporöses Material, p-tert-Butylcalix[4]aren, sorbiert Acetylen mit hoher Speicherdichte unter Umgebungsbedingungen. Es wird angenommen, dass die Gasmoleküle durch das Kristallgitter diffundieren, ohne die Anordnung der Wirtmoleküle aufzubrechen (siehe Bild; O rot, C blau, Hohlräume gelb).
Co-reporter:Michael W. Heaven;Gareth W. V. Cave Dr.;Robert M. McKinlay;Jochen Antesberger;Scott J. Dalgarno Dr.;Praveen K. Thallapally Dr.
Angewandte Chemie 2006 Volume 118(Issue 37) pp:
Publication Date(Web):25 JUL 2006
DOI:10.1002/ange.200600671
In die Röhre geschaut: Hexamere Nanokapseln aus wasserstoffbrückengebundenen Pyrogallol[4]arenen organisieren sich zu Sphären (A), Röhren und Kombinationen der beiden (B) im Sub-Mikrometermaßstab. Diese Ensembles wurden durch dynamische Lichtstreuung, Rasterelektronenmikroskopie, Transmissionselektronenmikroskopie (TEM) und Rasterkraftmikroskopie charakterisiert (unten rechts im Bild: TEM-Aufnahme einer röhrenförmigen Verbindung zwischen zwei Sphären).
Co-reporter:Michael W. Heaven;Gareth W. V. Cave Dr.;Robert M. McKinlay;Jochen Antesberger;Scott J. Dalgarno Dr.;Praveen K. Thallapally Dr.
Angewandte Chemie International Edition 2006 Volume 45(Issue 37) pp:
Publication Date(Web):25 JUL 2006
DOI:10.1002/anie.200600671
Six packs: Hydrogen-bonded pyrogallol[4]arene hexameric nanocapsules self-assemble into spheres (A; see picture), tubules, and combinations of both (B) on the sub-micron scale. These assemblies were characterized by using dynamic light scattering, scanning electron microscopy, transmission electron microscopy (see inset), and atomic force microscopy techniques.
Co-reporter:Praveen K. Thallapally Dr.;Liliana Dobrzańska Dr.;Todd R. Gingrich;Trevor B. Wirsig;Leonard J. Barbour
Angewandte Chemie International Edition 2006 Volume 45(Issue 39) pp:
Publication Date(Web):5 SEP 2006
DOI:10.1002/anie.200601391
Unusual storage: An organic nonporous material, p-tert-butylcalix[4]arene, sorbs acetylene with high storage density under ambient conditions. It is presumed that gas molecules diffuse through the seemingly nonporous lattice without disrupting the arrangement of the host molecules (see picture; red O, blue C, gray H, yellow void space).
Co-reporter:Scott J. Dalgarno, Gareth W. V. Cave,Jerry L. Atwood
Angewandte Chemie International Edition 2006 45(4) pp:570-574
Publication Date(Web):
DOI:10.1002/anie.200503035
Co-reporter:Scott J. Dalgarno Dr.;Daniel B. Bassil;Sheryl A. Tucker Dr.
Angewandte Chemie International Edition 2006 Volume 45(Issue 42) pp:
Publication Date(Web):2 OCT 2006
DOI:10.1002/anie.200601961
Throwing light on encapsulation: The fluorescent probe molecule 4-[3-(9-anthryl)propyl]-N,N-dimethylaniline (C gray, N blue) crystallizes either exo or endo to the cavity of pyrogallol[4]arene hexamers (O red) and displays markedly different fluorescence emission behavior as a result. In the exo array, the guest alters the packing of the hexamer by forming channels through the extended structure in the solid state (see picture).
Co-reporter:Scott J. Dalgarno;Sheryl A. Tucker;Daniel B. Bassil
Science 2005 Vol 309(5743) pp:2037-2039
Publication Date(Web):23 Sep 2005
DOI:10.1126/science.1116579
Abstract
Despite recent strides in the synthesis of elaborate nanometer-scale molecular hosts, the internal structure of these self-assembled cages remains ill characterized. We used fluorescent probe molecules, pyrene butyric acid (PBA), as guests in C-hexylpyrogallol[4]arene capsules to relay information about the chemical environment on the interior of the assemblies. Spectroscopic and single-crystal x-ray diffraction studies show that, in both solution and the solid state, the host can encapsulate two PBA guests and keep them well separated through specific interactions with the capsule walls.
Co-reporter:Jochen Antesberger, Gareth W. V. Cave, Matthew C. Ferrarelli, Michael W. Heaven, Colin L. Raston and Jerry L. Atwood
Chemical Communications 2005 (Issue 7) pp:892-894
Publication Date(Web):21 Jan 2005
DOI:10.1039/B412251H
The single step direct synthesis of pyrogallol[4]arene via a solvent free protocol yields the pure product as a self-assembled nano-capsule, comprised of six macrocyclic building blocks.
Co-reporter:Praveen K. Thallapally, Gareth O. Lloyd, Trevor B. Wirsig, Martin W. Bredenkamp, Jerry L. Atwood and Leonard J. Barbour
Chemical Communications 2005 (Issue 42) pp:5272-5274
Publication Date(Web):26 Sep 2005
DOI:10.1039/B511341E
We have studied the hydrogen sorption on three well-known organic hosts that possess vacant lattice voids large enough to accommodate H2 molecules.
Co-reporter:Praveen K. Thallapally, Trevor B. Wirsig, Leonard J. Barbour and Jerry L. Atwood
Chemical Communications 2005 (Issue 35) pp:4420-4422
Publication Date(Web):29 Jul 2005
DOI:10.1039/B507406A
The low density polymorph of the well-known host p-tert-butylcalix[4]arene absorbs more methane than p-tert-pentylcalix[4]arene at room temperature and 1 atm pressure, but the order of absorption is reversed at 38 atm with p-tert-pentylcalix[4]arene absorbing more.
Co-reporter:Jerry L. Atwood, Leonard J. Barbour, Praveen K. Thallapally and Trevor B. Wirsig
Chemical Communications 2005 (Issue 1) pp:51-53
Publication Date(Web):30 Nov 2004
DOI:10.1039/B416752J
A well-known host compound readily absorbs methane at room temperature and pressures of one atmosphere and lower.
Co-reporter:Gareth W. V. Cave, Matthew C. Ferrarelli and Jerry L. Atwood
Chemical Communications 2005 (Issue 22) pp:2787-2789
Publication Date(Web):18 Apr 2005
DOI:10.1039/B413829E
The cup-like cavity of pyrogallol[4]arenes has been deepened by the addition of four hydrogen bonded bipyridine molecules to the upper-rim of the calixarene, enabling the extended cup-like molecules to stack inside one another and consequently trap and completely enshroud a single guest molecule within the 250 Å3 cavitand formed between two of these stacked “nano-cups”.
Co-reporter:Robert M. McKinlay;Praveen K. Thallapally Dr.;Gareth W. V. Cave Dr.
Angewandte Chemie International Edition 2005 Volume 44(Issue 35) pp:
Publication Date(Web):4 AUG 2005
DOI:10.1002/anie.200501491
Uncommon water chain: A large neutral hexameric coordination cage [Ga12(H2O)24(C40H42O12)6⊂(acetone)8(H2O)6] is assembled from six pyrogallol[4]arene ligands and twelve GaIII ions. Found within the capsule structure are two pseudo-linear hydrogen-bonded water (H2O)5 chains (see picture, Ga gold, O red).
Co-reporter:Praveen K. Thallapally Dr.;Gareth O. Lloyd ;Leonard J. Barbour
Angewandte Chemie 2005 Volume 117(Issue 25) pp:
Publication Date(Web):13 MAY 2005
DOI:10.1002/ange.200500749
Wasser gräbt sich ein: Die durch Sublimation erhaltene Apo-Wirt-Phase eines substituierten hydrophoben Calixarens bildet Gitterhohlräume, aber keine Kanäle. Setzt man die Kristalle flüssigem Wasser aus, tritt eine Einkristall-Einkristall-Phasenumwandlung ein, bei der Wassermoleküle in die Hohlräume eingelagert werden (siehe Bild); somit ist die klassische Vorstellung der Diffusion möglicherweise auf atomarer Ebene nicht richtig.
Co-reporter:Robert M. McKinlay;Praveen K. Thallapally Dr.;Gareth W. V. Cave Dr.
Angewandte Chemie 2005 Volume 117(Issue 35) pp:
Publication Date(Web):4 AUG 2005
DOI:10.1002/ange.200501491
Ungewöhnliche H2O-Kette: Große neutrale hexamere Koordinationskäfige [Ga12(H2O)24(C40H42O12)6⊂(Aceton)8(H2O)6] werden aus sechs Pyrogallol[4]aren-Liganden und zwölf Gallium(III)-Ionen aufgebaut. Innerhalb der Kapselstruktur liegen zwei pseudo-lineare wasserstoffverbrückte (H2O)5-Ketten vor (siehe Bild; Ga gold, O rot).
Co-reporter:Praveen K. Thallapally Dr.;Gareth O. Lloyd ;Leonard J. Barbour
Angewandte Chemie International Edition 2005 Volume 44(Issue 25) pp:
Publication Date(Web):13 MAY 2005
DOI:10.1002/anie.200500749
Burrowing water: The apohost phase of a substituted hydrophobic calixarene, grown by sublimation, forms lattice voids but not channels. Exposure of the crystals to liquid water results in a single-crystal-to-single-crystal phase transformation during which water molecules become embedded in the lattice voids (see picture); thus the classical view of diffusion might not be appropriate at the atomic scale.
Co-reporter:Robert M. McKinlay;Gareth W. V. Cave
PNAS 2005 Volume 102 (Issue 17 ) pp:5944-5948
Publication Date(Web):2005-04-26
DOI:10.1073/pnas.0408113102
An important problem in designing any large network is the assembly of systems that are resilient to change. From a chemical
point of view, an analogy can be used where one requires supramolecular assemblies to maintain their dimensionality combined
with limited structural perturbation in response to variation in its intermolecular framework. The identification of hydrogen-bonded
framework patterns within experimentally known supramolecular assemblies that are structurally robust to disruption and selective
hydrogen substitution are envisioned to act as a supramolecular blueprint or template for metal-ion retroinsertion. Here,
we report the formation of a large neutral discrete pseudo-spherical coordination capsule assembled from 6 pyrogallol[4]arene
ligands and 24 Cu(II) metal ions. Amazingly, this coordination capsule is structurally analogous to its hydrogen-bonded counterpart.
This result shows a robust ability of pyrogallol[4]arene molecules to self-assemble into large hexameric cage structures from
either the hydrogen-bonding or metal-ligand coordination process. The identification of robust supramolecular assemblies that
conserve their structure in response to interchangeability between hydrogen-bonded networks for metal coordination, or inversely,
represents an important advancement in supramolecular design.
Co-reporter:Jerry L. Atwood, Leonard J. Barbour, Gareth O. Lloyd and Praveen K. Thallapally
Chemical Communications 2004 (Issue 8) pp:922-923
Publication Date(Web):24 Mar 2004
DOI:10.1039/B402452B
A low-density polymorph of the well-known host compound p-tert-butylcalix[4]arene undergoes subtle structural changes when heated and cooled.
Co-reporter:Gareth W. V. Cave Dr.;Jochen Antesberger;Leonard J. Barbour ;Robert M. McKinlay
Angewandte Chemie 2004 Volume 116(Issue 39) pp:
Publication Date(Web):29 SEP 2004
DOI:10.1002/ange.200490134
Co-reporter:Gareth W. V. Cave Dr.;Jochen Antesberger;Leonard J. Barbour ;Robert M. McKinlay
Angewandte Chemie 2004 Volume 116(Issue 39) pp:
Publication Date(Web):29 SEP 2004
DOI:10.1002/ange.200460711
Die leicht ablaufende Selbstorganisation von sechs Pyrogallol[4]aren-Molekülen führt zu einem nahezu kugelförmigen, abgestumpften Oktaeder, das Ethylacetat- und Wasser-Gastmoleküle einschließt (siehe Schema). Durch Derivatisierung der äußeren Kapseloberfläche kann die Wechselwirkung mit anderen Kapseln gesteuert werden.
Co-reporter:Jerry L. Atwood ;Leonard J. Barbour ;Agoston Jerga Dr.
Angewandte Chemie 2004 Volume 116(Issue 22) pp:
Publication Date(Web):19 MAY 2004
DOI:10.1002/ange.200353559
Gaswerke en miniature: Durch Sublimation gezüchtete p-tert-Butylcalix[4]aren-Kristalle verfügen über große interstitielle Cavitäten. Obwohl diese Festkörper nichtporös sind, können sie praktisch unter Standardbedingungen Gase wie O2, N2 und CO2 absorbieren und speichern. Da H2 nicht eingelagert wird, bietet sich das Material für die Trennung von H2 aus Gasgemischen an. Beim Evakuieren oder Eintauchen der Kristalle in Nitrobenzol (siehe Bild) werden die Gase wieder freigesetzt.
Co-reporter:Gareth W. V. Cave Dr.;Jochen Antesberger;Leonard J. Barbour ;Robert M. McKinlay
Angewandte Chemie International Edition 2004 Volume 43(Issue 39) pp:
Publication Date(Web):29 SEP 2004
DOI:10.1002/anie.200460711
The facile self-assembly of six pyrogallol[4]arene molecules leads to a globular truncated octahedron, which encapsulates a guest cluster consisting of ethyl acetate and water molecules (see scheme). The interactions between host capsules can be controlled by derivatization of the exterior surface of the capsule.
Co-reporter:Gareth W. V. Cave Dr.;Jochen Antesberger;Leonard J. Barbour ;Robert M. McKinlay
Angewandte Chemie International Edition 2004 Volume 43(Issue 39) pp:
Publication Date(Web):29 SEP 2004
DOI:10.1002/anie.200490135
Co-reporter:Jerry L. Atwood ;Leonard J. Barbour ;Agoston Jerga Dr.
Angewandte Chemie International Edition 2004 Volume 43(Issue 22) pp:
Publication Date(Web):19 MAY 2004
DOI:10.1002/anie.200353559
Molecular gas works:p-tert-Butylcalix[4]arene crystals possess large interstitial cavities when grown by sublimation and, although nonporous, are able to absorb and retain gases such as O2, N2, and CO2 under near-ambient conditions. H2 is not retained and thus the material can be used to effect the separation of H2 from gas mixtures. The gas can be removed by evacuation or immersion of the crystals in nitrobenzene (see picture).
Co-reporter:Jerry L. Atwood and Agnieszka Szumna
Chemical Communications 2003 (Issue 8) pp:940-941
Publication Date(Web):31 Mar 2003
DOI:10.1039/B301511D
A new approach to anion recognition utilizing electrostatic and hydrogen bonding interactions has been demonstrated by placement of the whole ion-pair in a molecular capsule.
Co-reporter:Jerry L. Atwood ;Leonard J. Barbour ;Michael W. Heaven;Colin L. Raston
Angewandte Chemie 2003 Volume 115(Issue 28) pp:
Publication Date(Web):16 JUL 2003
DOI:10.1002/ange.200351033
Eine Verunreinigung hilft bei der Reinigung von C60: Ein C60-Calix[5]aren-1:1-Komplex (siehe Bild) kristallisiert aus Toluol in Form eindimensionaler Zickzackketten aus Fullerenen, die von Calixaren-Molekülen umhüllt werden. Dieser Komplex bildet sich auch in Gegenwart anderer globulärer Moleküle wie C70, der Hauptverunreinigung in Fullerit.
Co-reporter:Jerry L. Atwood ;Leonard J. Barbour ;Michael W. Heaven;Colin L. Raston
Angewandte Chemie International Edition 2003 Volume 42(Issue 28) pp:
Publication Date(Web):16 JUL 2003
DOI:10.1002/anie.200351033
An impurity aids in the purification of C60. A 1:1 complex of C60 and calix[5]arene crystallizes from toluene (see picture) with the fullerenes organized in a one-dimensional zigzag array shrouded by a sheath of calixarenes. The complex forms in the presence of other globular molecules including C70, the major impurity in fullerite.
Co-reporter:Leonard J. Barbour;Agoston Jerga
PNAS 2002 Volume 99 (Issue 8 ) pp:4837-4841
Publication Date(Web):2002-04-16
DOI:10.1073/pnas.082659799
The enclosure of functional entities within a protective boundary is an essential feature of biological systems. On a molecular
scale, free-standing capsules with an internal volume sufficiently large to house molecular species have been synthesized
and studied for more than a decade. These capsules have been prepared by either covalent synthesis or self-assembly, and the
internal volumes have ranged from 200 to 1,500 Å3. Although biological systems possess a remarkable degree of order within the protective boundaries, to date only steric constraints
have been used to order the guests within molecular capsules. In this article we describe the synthesis and characterization
of hexameric molecular capsules held together by hydrogen bonding. These capsules possess internal order of the guests brought
about by hydrogen bond donors within, but not used by, the framework of the capsule. The basic building blocks of the hexameric
capsules are tetrameric macrocycles related to resorcin[4]arenes and pyrogallol[4]arenes. The former contain four 1,3-dihydroxybenzene
rings bridged together by -CHR- units, whereas the latter contain four 1,2,3-trihydroxybenzene rings bridged together. We
now report the synthesis of related mixed macrocycles, and the main focus is on the macrocycle composed of three 1,2,3-trihydroxybenzene
rings and one 1,3-dihydroxybenzene ring bridged together. The mixed macrocycles self-assemble from a mixture of closely related
compounds to form the hexameric capsule with internally ordered guests.
Co-reporter:Jerry L Atwood, Agnieszka Szumna
Journal of Supramolecular Chemistry 2002 Volume 2(4–5) pp:479-482
Publication Date(Web):August–October 2002
DOI:10.1016/S1472-7862(03)00068-6
The interaction of the neutral form of resorcin[4]arene 1 (R=i-Bu) with tetraalkylammonium cations (Me4N+, Et4N+, Pr4N+and Bu4N+) was analyzed in the solid state and in methanol solutions. In methanol, NMR titration results indicate almost no differentiation between Me4N+ and Et4N+ cations (Kass(Me4N+)=93 M−1 and Kass(Et4N+)=81 M−1) and a relatively low association constant for Pr4N+( Kass(Pr4N+)=25 M−1). In the solid state, for the Me4NCl complex, the resorcinarene assumes the C2v boat conformation and is surrounded by as many as four Me4NCl moieties. The structure of the Et4NCl complex indicates that ethyl group can be conveniently placed in the resocin[4]arene cavity. The larger Bu4N+ cation was found completely external to the cavity.The interaction of the neutral form of a resorcin[4]arene with tetraalkylammonium cations (Me4N+, Et4N+, Pr4N+and Bu4N+) was analyzed in the solid state and in methanol solutions.
Co-reporter:Jerry L. Atwood, Leonard J. Barbour and Agoston Jerga
Chemical Communications 2001 (Issue 22) pp:2376-2377
Publication Date(Web):19 Oct 2001
DOI:10.1039/B106250F
Robust, very large hydrogen-bonded capsules which are even stable in 50∶50 water–acetone mixtures have been characterized both in solution and in the solid state.
Co-reporter:Leonard J. Barbour and Jerry L. Atwood
Chemical Communications 2001 (Issue 19) pp:2020-2021
Publication Date(Web):18 Sep 2001
DOI:10.1039/B105182M
At low pH, and in the presence of 4,4′-bipyridine,
p-sulfonatocalix[4]arene crystallizes in the 1,3-alternate
conformation rather than the expected cone conformation and exhibits
remarkable stability.
Co-reporter:Jerry L Atwood, Leonard J Barbour, Agoston Jerga
Journal of Supramolecular Chemistry 2001 Volume 1(Issue 3) pp:131-134
Publication Date(Web):May–June 2001
DOI:10.1016/S1472-7862(02)00003-5
The acid-catalyzed condensation of pyrogallol and aldehydes yields pyrogallol[4]arenes, which associate in the form of hexameric capsules of extraordinary stability due to the presence of 48 intermolecular hydrogen bonds seaming the individual pyrogallol[4]arenes together.
Co-reporter:Leonard R MacGillivray, K.Travis Holman, Jerry L Atwood
Journal of Supramolecular Chemistry 2001 Volume 1(Issue 3) pp:125-130
Publication Date(Web):May–June 2001
DOI:10.1016/S1472-7862(02)00002-3
The self-assembly of C-methylresorcin[4]arene with 4,4′-bipyridine affords the formation of closed solid state cavities with internal volumes of ca. 1.0 nm3 which encapsulate up to an unprecedented 11 guests involving three different molecules. These cages exhibit functionality directed into the cavities, in the form of hydrogen bond donor and acceptor sites, which assists the organization of their guests. In one case, the guests interact, with each other and the walls of the host, via 15 hydrogen bonds, to produce chiral molecular assemblies within the solid.Graphic
Co-reporter:Leonard J. Barbour, G. William Orr and Jerry L. Atwood
Chemical Communications 2000 (Issue 10) pp:859-860
Publication Date(Web):05 May 2000
DOI:10.1039/B001862G
The conformation of a previously observed ice-like water
cluster in the solid state proves to be robust to geometric changes in its
surroundings and the hydrogen bonded arrangement is finally revealed in
detail.
Co-reporter:Harshita Kumari, Steven R. Kline, Drew A. Fowler, Andrew V. Mossine, Carol A. Deakyne and Jerry L. Atwood
Chemical Communications 2014 - vol. 50(Issue 1) pp:NaN111-111
Publication Date(Web):2013/11/05
DOI:10.1039/C3CC47029F
Giant nanocapsules: the solution-phase structures of PgC1Ho and PgC3Ho have been investigated using in situ neutron scattering measurements. The SANS results show the presence of spherical nanoassemblies of radius 18.2 Å, which are larger than the previously reported metal-seamed PgC3 hexamers (radius = 10 Å). The spherical architectures conform to a truncated cubeoctahedron geometry, indicating formation of the first metal-containing pyrogallol[4]arene-based dodecameric nanoassemblies in solution.
Co-reporter:Jian Tian, Praveen Thallapally, Jun Liu, Gregory J. Exarhos and Jerry L. Atwood
Chemical Communications 2011 - vol. 47(Issue 2) pp:NaN703-703
Publication Date(Web):2010/11/16
DOI:10.1039/C0CC04260A
A well-known organic host, tris-o-phenylenedioxycyclotriphosphazene, exists in two polymorphic guest-free forms: the thermodynamic nonporous high-density phase and the kinetic nanoporous low-density phase. Simple pressurization of the high density phase with CO2 brings a solid-state transformation to the low density phase, resulting in significant expansion of the crystal volume by 23%.
Co-reporter:Ping Jin, Harshita Kumari, Stuart Kennedy, Charles L. Barnes, Simon J. Teat, Scott J. Dalgarno and Jerry L. Atwood
Chemical Communications 2014 - vol. 50(Issue 34) pp:NaN4510-4510
Publication Date(Web):2014/03/24
DOI:10.1039/C4CC00202D
Addition of cadmium(II) nitrate to gallium-coordinated metal–organic C-alkylpyrogallol[4]arene nano-capsules affords a variation of the near spherical hexamer motif, structural changes in which are induced by the markedly different nature of the secondary incorporated metal.
Co-reporter:Harshita Kumari, Steven R. Kline and Jerry L. Atwood
Chemical Communications 2012 - vol. 48(Issue 30) pp:NaN3601-3601
Publication Date(Web):2012/02/14
DOI:10.1039/C2CC18071E
Solution structure of insulin templated C-methyl resorcin[4]arene nanocapsules has been investigated using neutron scattering. The insulin biotemplate has enhanced the limits of encapsulation and enabled formation of a larger spherical molecular host.
Co-reporter:Harshita Kumari, Steven R. Kline, Nathaniel J. Schuster and Jerry L. Atwood
Chemical Communications 2011 - vol. 47(Issue 45) pp:NaN12300-12300
Publication Date(Web):2011/10/25
DOI:10.1039/C1CC15615B
The stability of copper-seamed C-alkylpyrogallol[4]arene hexamers with varying chain lengths in solution has been studied using small-angle neutron scattering (SANS). The progression in diameter of spherical capsules with increasing alkyl chain lengths of copper-seamed hexamers in solution suggests both robustness as well as a close correlation between the solid phase and solution phase structures.
Co-reporter:Scott J. Dalgarno, Nicholas P. Power, John E. Warren and Jerry L. Atwood
Chemical Communications 2008(Issue 13) pp:NaN1541-1541
Publication Date(Web):2008/02/27
DOI:10.1039/B719769A
Metal–organic pyrogallol[4]arene nano-capsules, mixed pyrogallol[4]arene nano-capsules, and mixed metal analogues have been rapidly synthesised by addition of excess copper nitrate to a methanol solution of the corresponding macrocycle(s) (or gallium nano-capsules for the mixed metal system); improved solubility allows for thorough study and elucidation of the assembly process for these discrete metal–organic assemblies.
Co-reporter:Robert M. McKinlay, Scott J. Dalgarno, Peter J. Nichols, Stavroula Papadopoulos, Jerry L. Atwood and Colin L. Raston
Chemical Communications 2007(Issue 23) pp:NaN2395-2395
Publication Date(Web):2007/03/15
DOI:10.1039/B700984D
Hydrolysis of ‘tris(aryl or alkyl)gallium(III)’ species results in the formation of spheroidal dodecameric galloxane mixed oxide–hydroxide clusters, and shows that the gallium centres and associated residual alkyl/aryl groups are arranged at the polyhedral vertices of pseudo-icosahedra.
Co-reporter:Jerry L. Atwood, Euan K. Brechin, Scott J. Dalgarno, Ross Inglis, Leigh F. Jones, Andrew Mossine, Martin J. Paterson, Nicholas P. Power and Simon J. Teat
Chemical Communications 2010 - vol. 46(Issue 20) pp:NaN3486-3486
Publication Date(Web):2010/03/31
DOI:10.1039/C002247K
Nickel and cobalt seamed metal–organic capsules have been isolated and studied using structural, magnetic and computational approaches. Antiferromagnetic exchange in the Ni capsule results from coordination environments enforced by the capsule framework.
Co-reporter:Simon A. Herbert, Agnieszka Janiak, Praveen K. Thallapally, Jerry L. Atwood and Leonard J. Barbour
Chemical Communications 2014 - vol. 50(Issue 98) pp:NaN15512-15512
Publication Date(Web):2014/10/07
DOI:10.1039/C4CC07366E
The tetragonal apohost phase of p-tert-butyltetramethoxythiacalix[4]arene absorbs hydrochloric acid and iodine. These guest molecules occupy different sites in the solid-state structure – either within the small intrinsic voids of the macrocycle or within the interstitial spaces between the host molecules. This study illustrates the dynamic deformation of the host, providing strong mechanistic insight into the diffusion of guests into this seemingly non-porous material.
Co-reporter:Chen Zhang, Rahul S. Patil, Tao Li, Charles L. Barnes and Jerry L. Atwood
Chemical Communications 2017 - vol. 53(Issue 31) pp:NaN4314-4314
Publication Date(Web):2017/03/13
DOI:10.1039/C7CC01208J
The solvothermal synthesis of a metal-seamed hexameric nanocapsule from pyrogallol[4]arenes and magnesium is reported. The unique non-toxic and biocompatible nature of divalent magnesium cations in addition to the large inherent cavities make these nanocapsules promising for potential application in biomedicine. In addition, we show that these nanocapsules can form cocrystals with pyridine molecules through hydrogen bonding, which sheds light to cocrystallization of supramolecular nanocapsules with small pharmaceutics.
Co-reporter:Harshita Kumari, Steven R. Kline, Stuart R. Kennedy, Christopher Garvey, Colin L. Raston, Jerry L. Atwood and Jonathan W. Steed
Chemical Communications 2016 - vol. 52(Issue 24) pp:NaN4516-4516
Publication Date(Web):2016/02/25
DOI:10.1039/C6CC00171H
Vortex fluidic mediated shearing of supramolecular gels in thin films leads to complete disruption of fluorous bis-urea derived gels. Hydrocarbon analogues however, are only partially disrupted, which emphasizes the resistance of non-fluorous bis-urea gelators towards shear. The gel structures have been studied by combining the thin film shearing with small angle neutron scattering. This technique represents a novel approach to study the effects of external stimuli on self-assembled supramolecular gel networks.
Co-reporter:Scott J. Dalgarno, Praveen K. Thallapally, Leonard J. Barbour and Jerry L. Atwood
Chemical Society Reviews 2007 - vol. 36(Issue 2) pp:NaN245-245
Publication Date(Web):2007/01/02
DOI:10.1039/B606047C
Seemingly non-porous organic solids have the ability for guest transport and have also been shown to absorb gases, including hydrogen, methane and acetylene, to varied extents. These materials also show potential for gas separation technology, display remarkable water transport through hydrophobic crystals, and clearly show that molecules within crystals are capable of cooperating with guests as they move through non-porous environments. This work is presented within a broader topic which also encompasses crystal engineering and (microporous) metal-organic frameworks (MOF's).
Co-reporter:Ping Jin, Scott J. Dalgarno, John E. Warren, Simon J. Teat and Jerry L. Atwood
Chemical Communications 2009(Issue 23) pp:NaN3350-3350
Publication Date(Web):2009/05/19
DOI:10.1039/B822430G
The stepwise synthesis of mixed metal–organic C-alkylpyrogallol[4]arene nanocapsules allows control over the metal ratios in the resulting assembliesvia sequential incorporation and ejection of different metals.
Co-reporter:Scott J. Dalgarno, Karla M. Claudio-Bosque, John E. Warren, Timothy E. Glass and Jerry L. Atwood
Chemical Communications 2008(Issue 12) pp:NaN1412-1412
Publication Date(Web):2008/02/19
DOI:10.1039/B716777F
Reaction of p-carboxylatocalix[4]arene-O-methyl ether with either rubidium or caesium hydroxide results in the formation of interpenetrated nano-capsule networks with the calixarene in the 1,3-alternate conformation.
Co-reporter:Jian Tian, Shengqian Ma, Praveen K. Thallapally, Drew Fowler, B Peter McGrail and Jerry L. Atwood
Chemical Communications 2011 - vol. 47(Issue 27) pp:NaN7628-7628
Publication Date(Web):2011/06/10
DOI:10.1039/C1CC12689J
Cucurbit[7]uril (CB[7]), in its amorphous solid state, shows one of the highest CO2 sorption capacities among known organic porous materials at 298 K and 0.1 and 1 bar. In addition to the highest CO2 capacity, CB[7] also shows remarkable selectivity of CO2 over N2 and CH4. These properties, along with the existence of readily available precursors, indicate amorphous CB[7] might find applications in recycling CO2 particularly considering the easy synthesis and potentially low manufacturing costs.
Co-reporter:Praveen K. Thallapally, B. Peter McGrail and Jerry L. Atwood
Chemical Communications 2007(Issue 15) pp:NaN1523-1523
Publication Date(Web):2007/02/05
DOI:10.1039/B617340C
The uptake of various nitrogen oxides was studied with the well known nonporous p-tert-butylcalix[4]arene under ambient conditions.
Co-reporter:Scott J. Dalgarno, Jian Tian, John E. Warren, Thomas E. Clark, Mohamed Makha, Colin L. Raston and Jerry L. Atwood
Chemical Communications 2007(Issue 46) pp:NaN4850-4850
Publication Date(Web):2007/10/05
DOI:10.1039/B712621B
Varied temperature sublimation of calix[5]arene results in the formation of two distinctly different crystal structures or polymorphs α and β, the latter of which is based on both ‘self-included’ and ‘back-to-back’ helical arrangements of the molecule, while also being active towards CO2 sorption at room temperature and 1 atmosphere pressure.
Co-reporter:Scott J. Dalgarno, Nicholas P. Power and Jerry L. Atwood
Chemical Communications 2007(Issue 33) pp:NaN3449-3449
Publication Date(Web):2007/07/26
DOI:10.1039/B707009H
Ionic capsules based on dimeric arrangements of pyrogallol[4]arenes have been structurally authenticated and suggest that there is a degree of flexibility in capsule formation with further potential for multiple guest encapsulation and manipulation in such arrangements.
Co-reporter:Scott J. Dalgarno, Tamas Szabo, Ali Siavosh-Haghighi, Carol A. Deakyne, John E. Adams and Jerry L. Atwood
Chemical Communications 2009(Issue 11) pp:NaN1341-1341
Publication Date(Web):2009/01/09
DOI:10.1039/B819276F
Large fluorescent molecules have been encapsulated in pyrogallol[4]arene nano-capsules, thus exploring the limits of molecular encapsulation; the orientation of these probe molecules within these nano-capsules has been examined with additional computational approaches in one case.
Co-reporter:Drew A. Fowler, Simon J. Teat, Gary A. Baker and Jerry L. Atwood
Chemical Communications 2012 - vol. 48(Issue 43) pp:NaN5264-5264
Publication Date(Web):2012/03/30
DOI:10.1039/C2CC31510F
We report on a cocrystal between C-propyl pyrogallol[4]arene and the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate exhibiting a remarkable bilayer topology comprising two unique host–guest complexes resulting from the ionic liquid cation binding in two distinctive orientations relative to the macrocycle.
Co-reporter:Andrew K. Maerz, Haunani M. Thomas, Nicholas P. Power, Carol A. Deakyne and Jerry L. Atwood
Chemical Communications 2010 - vol. 46(Issue 8) pp:NaN1237-1237
Publication Date(Web):2010/01/15
DOI:10.1039/B921911K
An induced cis–trans–trans (rctt) chair to cone structural rearrangement is forced by the addition of a pentacoordinate zinc(II) complex, overcoming thermodynamic and kinetic factors to produce the first phenyl-substituted zinc dimeric nanocapsule.
Co-reporter:Rahul S. Patil, Harshita Kumari, Charles L. Barnes and Jerry L. Atwood
Chemical Communications 2015 - vol. 51(Issue 12) pp:NaN2307-2307
Publication Date(Web):2014/12/19
DOI:10.1039/C4CC08388A
Supramolecular organic frameworks (SOFs) based on pyrogallol[4]arene and 4,4′-bipyridine-type spacer molecules have been investigated. The hydrogen bonding pattern and molecular arrangement in the crystal structures are engineered through the cocrystallization approach. The length of the spacer molecules and the C-alkyl tail length of the PgC macrocycle are tuned to influence the hydrogen bonding pattern and thus the overall architecture of the resultant SOFs. Combined solid-state thermal analysis and solution-phase 1H NMR results indicate the amount of solvent loss and the stability of the SOFs in solution.
Co-reporter:Andrew V. Mossine, Collin M. Mayhan, Drew A. Fowler, Simon J. Teat, Carol A. Deakyne and Jerry L. Atwood
Chemical Science (2010-Present) 2014 - vol. 5(Issue 6) pp:NaN2303-2303
Publication Date(Web):2014/03/19
DOI:10.1039/C4SC00462K
The synthesis of a two-dimensional (2D) metal–organic framework (MOF) is described wherein Zn-seamed pyrogallol[4]arene (PgCx) nanocapsules are utilized as supramolecular building blocks with 4,4′-bipyridine (bpy) linkers. The choice of linker and of crystallization solvent (DMSO) was guided by electronic structure calculations on the zinc model complexes Zn(C2H3O2)2L, which showed that bpy and DMSO have similar Zn–L binding strengths and that there is little drop-off in binding strength when bpy is bound to a second Zn(C2H3O2)2 moiety. The MOF features unusual coordination geometries at the zinc centres along the nanocapsular periphery when compared to previous examples of zinc-seamed nanocapsules. The change in coordination geometry leads to a compulsory change in the internal volume of the nanocapsule as well as the behaviour of the encapsulated guest molecule. There are also several well defined voids and channels within the structure.
![PENTACYCLO[19.3.1.13,7.19,13.115,19]OCTACOSA-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-DODECAENE-4,5,6,10,11,12,16,17,18,22,23,24-DODECOL, 2,8,14,20-TETRAKIS(4-HYDROXYPHENYL)-](http://img.cochemist.com/ccimg/840600/840507-57-5.png)
![PENTACYCLO[19.3.1.13,7.19,13.115,19]OCTACOSA-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-DODECAENE-4,5,6,10,11,12,16,17,18,22,23,24-DODECOL, 2,8,14,20-TETRAKIS(4-HYDROXYPHENYL)-](http://img.cochemist.com/ccimg/840600/840507-57-5_b.png)
![Nonadecacyclo[53.17.3.37,25.313,67.319,37.331,49.343,61.12,6.18,12.114,18.120,
24.126,30.132,36.138,42.144,48.150,54.156,60.162,66.168,72]dohecta-2,4,6(102),8,
10,12(101),14,16,18(100),20,22,24(99),26,28,30(95),32,34,36(94),38,
40,42(90),44,46,48(89),50,52,54(85),56,58,60(84),62,64,66(80),68,70
,72(76)-hexatriacontaene-3,5,9,11,15,17,21,23,27,29,33,35,39,41,45,
47,51,53,57,59,63,65,69,71-tetracosol](http://img.cochemist.com/ccimg/862500/862494-04-0.png)
![Nonadecacyclo[53.17.3.37,25.313,67.319,37.331,49.343,61.12,6.18,12.114,18.120,
24.126,30.132,36.138,42.144,48.150,54.156,60.162,66.168,72]dohecta-2,4,6(102),8,
10,12(101),14,16,18(100),20,22,24(99),26,28,30(95),32,34,36(94),38,
40,42(90),44,46,48(89),50,52,54(85),56,58,60(84),62,64,66(80),68,70
,72(76)-hexatriacontaene-3,5,9,11,15,17,21,23,27,29,33,35,39,41,45,
47,51,53,57,59,63,65,69,71-tetracosol](http://img.cochemist.com/ccimg/862500/862494-04-0_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetrakis(2-phenylethyl)-](/data/chemimg/2648900/521959-41-1.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetrakis(2-phenylethyl)-](/data/chemimg/2648900/521959-41-1_b.png)
![PENTACYCLO[19.3.1.13,7.19,13.115,19]OCTACOSA-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-DODECAENE-4,5,6,10,11,12,16,17,18,22,23,24-DODECOL, 2,8,14,20-TETRAKIS(4-HYDROXYBUTYL)-](http://img.cochemist.com/ccimg/512800/512785-38-5.png)
![PENTACYCLO[19.3.1.13,7.19,13.115,19]OCTACOSA-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-DODECAENE-4,5,6,10,11,12,16,17,18,22,23,24-DODECOL, 2,8,14,20-TETRAKIS(4-HYDROXYBUTYL)-](http://img.cochemist.com/ccimg/512800/512785-38-5_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,6,10,12,16,18,22,24-octol, 2,8,14,20-tetrahexyl-](/data/chemimg/3724200/129831-84-1.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,6,10,12,16,18,22,24-octol, 2,8,14,20-tetrahexyl-](/data/chemimg/3724200/129831-84-1_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,6,10,12,16,18,22,24-octol, 2,8,14,20-tetrapropyl-](/data/chemimg/3724200/129831-83-0.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,6,10,12,16,18,22,24-octol, 2,8,14,20-tetrapropyl-](/data/chemimg/3724200/129831-83-0_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetraundecyl-](/data/chemimg/102400/127203-21-8.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetraundecyl-](/data/chemimg/102400/127203-21-8_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetramethyl-](/data/chemimg/3724200/137328-69-9.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetramethyl-](/data/chemimg/3724200/137328-69-9_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetraethyl-](/data/chemimg/3724200/133442-39-4.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetraethyl-](/data/chemimg/3724200/133442-39-4_b.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetrapropyl-](/data/chemimg/3724200/133352-88-2.png)
![Pentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,5,6,10,11,12,16,17,18,22,23,24-dodecol, 2,8,14,20-tetrapropyl-](/data/chemimg/3724200/133352-88-2_b.png)
