Co-reporter:Ting Ouyang, Cheng Hou, Jia-Wei Wang, Wen-Ju Liu, Di-Chang Zhong, Zhuo-Feng Ke, and Tong-Bu Lu
Inorganic Chemistry July 3, 2017 Volume 56(Issue 13) pp:7307-7307
Publication Date(Web):June 14, 2017
DOI:10.1021/acs.inorgchem.7b00566
Visible-light driven reduction of CO2 into chemical fuels has attracted enormous interest in the production of sustainable energy and reversal of the global warming trend. The main challenge in this field is the development of efficient, selective, and economic photocatalysts. Herein, we report a Co(II)-based homogeneous catalyst, [Co(NTB)CH3CN](ClO4)2 (1, NTB = tris(benzimidazolyl-2-methyl)amine), which shows high selectivity and stability for the catalytic reduction of CO2 to CO in a water-containing system driven by visible light, with turnover number (TON) and turnover frequency (TOF) values of 1179 and 0.032 s–1, respectively, and selectivity to CO of 97%. The high catalytic activity of 1 for photochemical CO2-to-CO conversion is supported by the results of electrochemical investigations and DFT calculations.
Co-reporter:Di-Chang Zhong;Yong-Liang Huang;Long Jiang;Yun-Nan Gong
Inorganic Chemistry January 17, 2017 Volume 56(Issue 2) pp:705-708
Publication Date(Web):December 29, 2016
DOI:10.1021/acs.inorgchem.6b02407
Two metal–organic frameworks (MOFs) {(Me2NH2)[ZnLi(PTCA)(H2O)]}n·n{3DMF·C4H8O2·4H2O} (1) and {(Me2NH2)[ZnLi(PTCA)]}n·n{3DMF·5H2O} (2) have been constructed from Li–Zn clusters and pyrene-1,3,6,8-tetracarboxylic acid (H4PTCA) under solvothermal conditions. Gas sorption measurements have revealed that the pore of desolvated 2 (2d) can strongly interact with H2 and CO2, with high H2 and CO2 adsorption heats of 15.3 and 51.9 kJ/mol, respectively. Furthermore, 2d can selectively adsorb CO2 over N2 and CH4, with high adsorption selectivity of CO2/N2 and CO2/CH4.
Co-reporter:Jian Wang, Jianying Yang, Zengyao Zheng, Tongbu Lu, Wenhua Gao
Applied Catalysis B: Environmental 2017 Volume 218(Volume 218) pp:
Publication Date(Web):5 December 2017
DOI:10.1016/j.apcatb.2017.06.042
•Formation of NiPi on hematite by a facile deposit-photoelectrochemical (DPEC).•regulation process.•Ti doped Fe2O3 possessed relatively rich oxygen vacancies after high temperature annealing, accountable for low photoactivity at low bias.•NiPi coating suppressed the surface states for improving the photoactivity at low bias.•The PEC property of NiPi was comparable with CoPi, CoPi coating couldn’t suppress the surface states.Ti doped hematite (α-Fe2O3) usually shows poor photoactivity compared with pristine Fe2O3 at less positive potential. Herein, a thin and relatively homogeneous nickle-hydroxyl-phosphate (NiPi) film was modified on Ti doped Fe2O3 electrode by a new deposit-photoelectrochemical (DPEC) regulation process for promoting hole transport at low bias. The role of Ti doping and NiPi or CoPi coating was studied by photoelectrochemical and electrochemical measurements in detail, in which NiPi coating suppressed the surface states, while CoPi coating couldn’t, Ti doped Fe2O3 possessed relatively rich oxygen vacancies after high temperature annealing, Ti doping only improved carrier density. Desirably, the performance of NiPi was comparable with CoPi. Additional test preliminarily verified that methanol was probably an more effective hole scavenger, while PO43− adsorbed Fe2O3/NiPi suppressed the oxidation of low-concentration glucose, resulting into high-energy glucose waste.Download high-res image (188KB)Download full-size image
Co-reporter:Jia-Wei Wang;Cheng Hou;Hai-Hua Huang;Wen-Ju Liu;Zhuo-Feng Ke
Catalysis Science & Technology (2011-Present) 2017 vol. 7(Issue 23) pp:5585-5593
Publication Date(Web):2017/11/27
DOI:10.1039/C7CY01527E
The development of efficient, robust and economical water oxidation catalysts (WOCs) remains a key challenge for water splitting. Herein, three macrocyclic nickel(II) complexes with four, six and eight methyl groups in the ligands have been utilized as homogeneous electrocatalysts for water oxidation in aqueous phosphate buffer at pH 7.0, in which the catalyst with eight methyl groups exhibits the highest catalytic activity, with a large current density of 1.0 mA cm−2 at 1.55 V vs. NHE (750 mV overpotential) in long-term electrolysis. The results of electrochemistry, UV-vis spectroelectrochemistry and DFT calculations suggest that the axially oriented methyl groups in the macrocyclic ligands with eight and six methyl groups can impose a steric effect on the axial position of the NiIII center, which not only results in higher NiIII/II oxidation potentials but also suppresses the axial coordination of phosphate anions with the NiIII center to achieve better catalytic performance. Such a steric effect in homogeneous WOCs has not been reported so far.
Co-reporter:Yun-Nan Gong, Ting Ouyang, Chun-Ting He and Tong-Bu Lu
Chemical Science 2016 vol. 7(Issue 2) pp:1070-1075
Publication Date(Web):11 Nov 2015
DOI:10.1039/C5SC02679B
A major challenge for the development of organic water oxidation catalysts is their low chemical stability and low catalytic efficiency. Herein, we first demonstrate that both the chemical stability and catalytic efficiency of an organic ligand for water oxidation can be improved by incorporating it into the framework of a stable MOF. This opens up a promising avenue for the development of stable and efficient organic water oxidation catalysts.
Co-reporter:Jia-Wei Wang, Pathik Sahoo, and Tong-Bu Lu
ACS Catalysis 2016 Volume 6(Issue 8) pp:5062
Publication Date(Web):June 27, 2016
DOI:10.1021/acscatal.6b00798
Recently, a dinuclear cobalt complex, [(TPA)CoIII(μ-OH)(μ-O2)CoIII(TPA)](ClO4)3 (1; TPA = tris(2-pyridylmethyl)amine), has been reported as a homogeneous catalyst for electrochemical and photochemical water oxidation ( Angew. Chem. Int. Ed. 2014, 53, 14499). During the reinvestigation of the reported water oxidation catalyst (WOC) of 1, several characterizations such as EDTA and bipyridine titrations, electrochemistry, SEM, EDX, ICP-AES, TEM, XPS, and UV–vis spectroscopy have revealed that the water oxidation may happen due to the formation of CoOx as a real heterogeneous WOC, and 1 itself lacks the ability to catalyze water oxidation. This paper presents a practical and simple procedure to clarify whether the water oxidation is truly catalyzed by a molecular catalyst or not.Keywords: cobalt oxide; dinuclear cobalt complex; electrocatalysis; heterogeneous versus homogeneous water oxidation catalysis; identification; photocatalysis
Co-reporter:Mei Zhang, Yong-Liang Huang, Jia-Wei Wang and Tong-Bu Lu
Journal of Materials Chemistry A 2016 vol. 4(Issue 5) pp:1819-1827
Publication Date(Web):14 Jan 2016
DOI:10.1039/C5TA07813J
A main challenge for light-driven water splitting is the development of efficient and economical water oxidation catalysts (WOCs). Herein, we developed a facile approach for the preparation of a porous cobalt oxide–carbon hybrid, which was prepared by carbonizing in an inert atmosphere and subsequently air-calcining nanocrystals of zeolite imidazole framework-67 (ZIF-67), and utilized as an efficient WOC. Using Ru(bpy)3(PF6)3 as an oxidant, we got a record catalytic turnover number (TON) and a turnover frequency (TOF) of 910 ± 21 and 14.6 ± 0.4 s−1 per cobalt atom, respectively. In addition, the synthesized catalyst can also act as an efficient electrochemical WOC, with a low OER overpotential of 0.36 V at 10.0 mA cm−2 in a pH 13 medium. The superior catalyst performance can be attributed to the homogeneous dispersion of CoOx and in situ formed porous carbon, and the presence of nitrogen in the catalyst may also be attributed to its high catalytic activity.
Co-reporter:Di-Chang Zhong and Tong-Bu Lu
Chemical Communications 2016 vol. 52(Issue 68) pp:10322-10337
Publication Date(Web):22 Jun 2016
DOI:10.1039/C6CC03660K
The design and syntheses of supramolecular hosts for the recognition and activation of molecules and anions are one of the most active research fields in supramolecular chemistry, in which polyaza macrocyclic ligands and their complexes have drawn particular attention due to their strong host–guest interactions. This review mainly focuses on the recent progress in the recognition of molecules and anions by polyaza macrocyclic compounds including polyaza macrocycles, polyaza macrobicycles and polyaza macrotricycles, as well as the activation of molecules by polyaza macrocyclic ligands and their metal complexes.
Co-reporter:Yun-Nan Gong, Di-Chang Zhong and Tong-Bu Lu
CrystEngComm 2016 vol. 18(Issue 15) pp:2596-2606
Publication Date(Web):08 Mar 2016
DOI:10.1039/C6CE00371K
Interpenetration usually refers to two or more individual polymeric networks with the same or different components catenated with each other, which is a frequently observed phenomenon in metal–organic frameworks (MOFs). The interpenetrating metal–organic frameworks (IMOFs) show fascinating architectures and topologies, as well as exhibit improved functions and applications. In this highlight, we summarize the recent advances in IMOFs, including homo- and hetero-IMOFs.
Co-reporter:Yong Chen, Long Li, Jia Yao, Yu-Yu Ma, Jia-Mei Chen, and Tong-Bu Lu
Crystal Growth & Design 2016 Volume 16(Issue 5) pp:2923-2930
Publication Date(Web):March 31, 2016
DOI:10.1021/acs.cgd.6b00266
Apixaban (apx), with a trade name of Eliquis, is a highly selective and efficacious inhibitor of blood coagulation factor Xa. Apixaban has poor solubility in water (0.028 mg/mL at 24 °C) and a relatively low oral bioavailability (about 50% for a single 10 mg dose). The purpose of this study is to improve the solubility and consequently the oral bioavailability of apixaban via a cocrystal. A cocrystal of apixaban with oxalic acid (apx-oxa-H2O, 4:3:0.5) was successfully obtained and characterized. The structure of the cocrystal was determined by single-crystal X-ray diffraction. The solubility of the cocrystal in 0.1 M HCl (pH 1.0) and phosphate buffer of pH 6.8 was evaluated, and the results show the solubility values of the cocrystal are approximately 2.2 and 2.1 times as large as those of apixaban form N-1 (the marketed product), respectively. The pharmacokinetics in beagle dogs was also investigated, and the mean AUC0–24h of the cocrystal is approximately 2.7 times as large as that of apixaban form N-1, indicating that both solubility and bioavailability of apixaban can be improved via a cocrystal.
Co-reporter:Yong-Liang Huang;Dr. Long Jiang ; Tong-Bu Lu
ChemPlusChem 2016 Volume 81( Issue 8) pp:780-785
Publication Date(Web):
DOI:10.1002/cplu.201600121
Abstract
A novel 3D anionic metal–organic framework (MOF) of (Me2NH2)4[Ni8(PTCA)4(μ3-OH)4(H2O)4](DMF)5(H2O)13 (H4PTCA=pyrene-1,3,6,8-tetracarboxylic acid) has been synthesized, in which Me2NH2+ can be exchanged by Li+ ions. The results of gas sorption measurements indicate that the desolvated MOFs both before and after Li+ exchange show highly selective adsorption for CO2 over CH4 and N2 gases, and the Li+-exchanged MOF exhibits enhanced CO2, CH4, and H2 storage properties.
Co-reporter:Gang-Yi Luo;Hai-Hua Huang;Jia-Wei Wang ; Tong-Bu Lu
ChemSusChem 2016 Volume 9( Issue 5) pp:485-491
Publication Date(Web):
DOI:10.1002/cssc.201501474
Abstract
The reaction of N,N′-dimethyl-N,N′-bis(pyridin-2-ylmethyl)-1,2-diaminoethane ligand (L) with Ni(ClO4)2⋅6 H2O generated a complex of [NiL(H2O)2](ClO4)2 (1) with two cis labile sites occupied by two coordinated H2O molecules, which can homogeneously electrocatalyze water oxidation in pH 6.5 acetate (OAc−) buffer at room temperature. The catalytic mechanism was studied by electrochemical experiments and density functional theory calculations to elucidate the following steps: (a) one of two water molecules in 1 is exchanged by OAc− to generate [NiL(H2O)(OAc)]+ when dissolved in OAc− buffer, (b) NiII is directly oxidized to NiIV and OAc− is replaced with OH− to form [NiIVL(OH)2]2+, and (c) a peroxide intermediate is formed through the intramolecular O−O coupling in the presence of OAc−, which undergoes further oxidation to release O2.
Co-reporter:Ping Ju, Long Jiang, and Tong-Bu Lu
Inorganic Chemistry 2015 Volume 54(Issue 13) pp:6291-6295
Publication Date(Web):June 17, 2015
DOI:10.1021/acs.inorgchem.5b00592
A three-dimensional metal–organic framework (1) with fourfold interpenetrating diamondoid networks was constructed using a macrocyclic nickel(II) complex and a tetracarboxylic ligand 4,4′,4″,4‴-(cyclohexane-1,2-diyibis(azanetriyl))tetrakis(methylene)tetrabenzoic acid as building blocks. Despite the fourfold interpenetration, 1 possesses one-dimensional channels that are occupied by water and CH3CN guest molecules. Once the guest molecules were removed, the framework and pores in desolvated 1 are dynamic with large adsorption hysteresis loops, which exhibit selective gas adsorption for CO2 at 195 K over N2 and H2 at 77 K and selective adsorption for methanol, ethanol, and n-propanol over isopropanol at 298 K.
Co-reporter:Yun-Nan Gong, Yong-Rong Xie, Di-Chang Zhong, Zi-Yi Du, and Tong-Bu Lu
Crystal Growth & Design 2015 Volume 15(Issue 7) pp:3119
Publication Date(Web):June 9, 2015
DOI:10.1021/acs.cgd.5b00634
A luminescent porous metal–organic framework based on π-electron-rich tricarboxylate has been solvothermally prepared and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analyses, and single-crystal X-ray diffraction analysis. This compound is a 2-fold interpenetrating framework with a large solvent-accessible volume and exhibits gas sorption behaviors for N2, H2, and CO2 gases and relatively strong interactions between CO2 and the framework. Furthermore, it also shows interesting guest-responsive luminescent changes toward different solvent molecules.
Co-reporter:Feng Yan, Xiao-Mei Zhuang and Tong-Bu Lu
CrystEngComm 2015 vol. 17(Issue 30) pp:5832-5840
Publication Date(Web):08 Jul 2015
DOI:10.1039/C5CE00817D
The crystal structures of eight cascade complexes, [Zn2L(μ-Cl)](ClO4)3·2H2O·3CH3CN (1), [Zn2L(μ-Br)](ClO4)3·2H2O·3CH3CN (2), [Cd2L(μ-OH)]2[CdI4]3·6DMF (3), [Cd2L(μ-Cl)][CdCl4](Cl)·4.5H2O (5), [Cd2L(μ-Br)][CdBr4](Br)·1.5H2O (6), [Hg2L(μ-Cl)][HgCl4](Cl)·6H2O (9), [Hg2L(μ-Br)][HgBr4](Br)·1.25H2O (10), and [Hg2L(μ-I)](NO3)3·6H2O (11), were presented, which reveal the influence of the coordinated metal ions on the selectivity in the cascade binding mode. The dizinc(II) cryptate shows the recognition of Cl− and Br− rather than that of F− and I−. Unexpectedly, the dicadmium(II) cryptate shows the recognition of OH−, F−, Cl− and Br− rather than that of I−, while all of the above-mentioned anions can form stable cascade complexes with the dimercury(II) cryptate. For better understanding, the binding behaviors and stabilisation energies between [M2L]4+ and anions were calculated by DFT calculations.
Co-reporter:Ai-Yan Li, Lin-Lin Xu, Jia-Mei Chen, and Tong-Bu Lu
Crystal Growth & Design 2015 Volume 15(Issue 8) pp:3785
Publication Date(Web):July 2, 2015
DOI:10.1021/acs.cgd.5b00439
A potassium-sparing diuretic, triamterene, shows a low oral bioavailability with wide intersubject variation due to its poor aqueous solubility (45 μg/mL). To improve its solubility, a group of pharmaceutically acceptable coformers were screened with triamterene by slurry and liquid-assisted grinding methods, and dl-mandelic acid (1) and saccharin (2) successfully cocrystallized with triamterene to form one anhydrous and one monohydrate molecular salt, respectively. Both new forms were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Their single crystal structures reveal that proton transfer from coformers to the nitrogen atom of the pyrimidine group in triamterene and the coformer anions thus connect to the protonated triamterene by multiple hydrogen bonded heterosynthons. The apparent solubility values and intrinsic dissolution rates of 1 and 2 in simulated gastric fluid (pH 1.20) are higher than those of parent drug, indicating the solubility of triamterene can be effectively improved by cocrystallization. The exposure of 1 and 2 to 0–95% RH levels and accelerated ICH condition of 40 °C/75% RH confirm their stability and the potential of these new forms to envisage new, more efficient formulations of triamterene.
Co-reporter:Jia-Xi Song, Jia-Mei Chen, and Tong-Bu Lu
Crystal Growth & Design 2015 Volume 15(Issue 10) pp:4869-4875
Publication Date(Web):August 28, 2015
DOI:10.1021/acs.cgd.5b00699
Pharmaceutical cocrystals are an efficient approach to improve the solubility of insoluble active pharmaceutical ingredients (APIs), while the dissolution profiles of pharmaceutical cocrystals usually exhibit a type of “spring and rapid parachute” effect that influences stability and pharmacodynamic sustainability, in which the high apparent solubility induced by the formation of cocrystals can only be maintained for a short time (usually minutes) in the metastable zone and then decreases rapidly afterwords. Herein we reported the preparation and structures of two lenalidomide cocrystals with gallic acid (1, 2). After the formation of cocrystals, the intrinsic dissolution rate and apparent solubility of lenalidomide were found to be enhanced. The high solubility of cocrystals can keep for 48 h without dropping. The result of phase solubility study indicates gallic acid (GA) forms a 1:1 complex with lenalidomide (Rev) in aqueous solution, with a stability constant of 1713.2 L/mol. The multiple hydrogen bonding interactions between GA and Rev are attributed to the formation of GA-Rev complex in aqueous solution and subsequently the constant high solubility of cocrystals.
Co-reporter:Yun-Nan Gong, Yong-Liang Huang, Long Jiang, and Tong-Bu Lu
Inorganic Chemistry 2014 Volume 53(Issue 18) pp:9457-9459
Publication Date(Web):August 29, 2014
DOI:10.1021/ic501413r
A luminescent microporous metal–organic framework based on a π-electron-rich tricarboxylate ligand and an In3+ ion has been solvothermally obtained and characterized and exhibits highly selective CO2 adsorption over CH4 and N2 gases and selective sensing of the nitro explosive 2,4,6-trinitrophenol.
Co-reporter:Song Li, Jia-Mei Chen and Tong-Bu Lu
CrystEngComm 2014 vol. 16(Issue 28) pp:6450-6458
Publication Date(Web):09 Apr 2014
DOI:10.1039/C4CE00221K
Although polymorphism is a common phenomenon, the polymorphism of co-crystals is not studied extensively as compared to single-component molecules. Herein we report polymorphism in a co-crystal system comprising 5-fluorouracil, and 4-hydroxybenzoic acid with a 1:1 stoichiometry. The polymorphs were characterized by single-crystal and powder X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis. Crystal structure analysis revealed different synthons of 5-fluorouracil and 4-hydroxybenzoic acid in two forms. The solvent-drop grinding experiments show a high degree of solvent polarity specificity. The theoretical and experimental methods suggest an enantiotropic relationship between the polymorphs.
Co-reporter:Jia-Mei Chen, Song Li, and Tong-Bu Lu
Crystal Growth & Design 2014 Volume 14(Issue 12) pp:6399-6408
Publication Date(Web):October 31, 2014
DOI:10.1021/cg501247x
Cocrystals have been extensively utilized to improve drugs’ properties. Ribavirin is a water-soluble broad-spectrum antiviral drug and its application is severely limited by the peak-to-trough fluctuation in plasma drug concentrations and some undesirable side-effects. We show here that formation of cocrystals may be a useful approach to overcome this problem by reducing the release rate of ribavirin. Three cocrystals of ribavirin with 3,5-dihydroxybenzoic acid (1), gallic acid (2), and barbituric acid (3) were successfully prepared and characterized by powder and single crystal X-ray diffraction, infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis, as well as dynamic vapor sorption measurement. The dissolution process revealed that 1–3 showed a reduced release rate as compared to ribavirin in the buffer solution representing intestinal pH 6.8. This study indicates that the release rate of ribavirin can be manipulated over a wide range by the formation of cocrystals, which may subsequently help lower its peak-to-trough fluctuation in plasma concentrations.
Co-reporter:Jia Yao, Yong-Hui Mo, Jia-Mei Chen, and Tong-Bu Lu
Crystal Growth & Design 2014 Volume 14(Issue 5) pp:2599-2604
Publication Date(Web):April 24, 2014
DOI:10.1021/cg500302h
Captopril is an antihypertension drug, it has side effects of vertigo, headache, and functional gastrointestinal disorders due to its overhigh plasma concentration. In addition, captopril undergoes oxidation at its thiol to yield captopril disulfide. In order to reduce its release rate and increase its oxidation stability, coordination polymer of captopril with zinc ion was prepared and its structure was determined by single crystal X-ray diffraction. The results of solubility measurements indicate that the apparent solubility and intrinsic dissolution rate of captopril can be dramatically decreased after the formation of coordination polymer. Pharmacokinetic studies in rats reveal that the plasma concentration of captopril can be reduced by the formation of zinc coordination polymer, with maximum plasma concentration reduced from 2.53 μg/mL for captopril to 0.99 μg/mL for the zinc coordination polymer. Moreover, the oxidation stability of captopril is simultaneously improved by the formation of zinc coordination polymer.
Co-reporter:Jia-Xi Song, Yan Yan, Jia Yao, Jia-Mei Chen, and Tong-Bu Lu
Crystal Growth & Design 2014 Volume 14(Issue 6) pp:3069-3077
Publication Date(Web):May 7, 2014
DOI:10.1021/cg500327s
An anticancer drug, lenalidomide, has low oral bioavailability (below 33%) due to its poor solubility in water. To improve its solubility, three cocrystals of lenalidomide with urea (1) and 3,5-dihydroxybenzoic acid (2, 3) were prepared. The structures of 1–3 were determined by single crystal X-ray diffraction, and they all form three-dimensional hydrogen-bonded frameworks between lenalidomide and the coformers. The apparent solubility value and intrinsic dissolution rate of lenalidomide in phosphate buffer of pH 6.8 have been improved after the formation of cocrystals. In addition, 2 and 3 can convert to each other under certain conditions.
Co-reporter:Jia Yao, Jia-Mei Chen, Yi-Bo Xu, and Tong-Bu Lu
Crystal Growth & Design 2014 Volume 14(Issue 10) pp:5019-5025
Publication Date(Web):September 18, 2014
DOI:10.1021/cg5005819
An antitumor drug, 6-mercaptopurine monohydrate (MP·H2O), has a low oral bioavailability due to its poor aqueous solubility. In order to improve its solubility, two ionic cocrystals of 6-mercaptopurine with zinc trifluoromethanesulfonate (Zn(CF3SO3)2), [Zn(MP)2(H2O)2](CF3SO3)2·2H2O (1) and [Zn(MP)2](CF3SO3)2 (2), were prepared. Slow evaporation of the methanol solution containing 1 gave the crystals of [Zn(MP)2(H2O)(MeOH)](CF3SO3)2·H2O (1a). Single-crystal-to-single-crystal transformation occurred under certain conditions, in which 1a transformed to 1 in the open air around 10 °C, and 1 further transformed to [Zn(MP)2(H2O)](CF3SO3)2 (1b) at room temperature (∼25 °C) and low RH%. The structures of 1, 1a, and 1b were determined by single crystal X-ray diffraction, in which MP and Zn(CF3SO3)2 were assembled via coordination bonds and hydrogen bonds, and the coordination geometry of Zn(II) changed from octahedron in 1 and 1a to square pyramid in 1b. After the formation of ionic cocrystals of 1 and 2, both the apparent solubility and dissolution rate were increased.
Co-reporter:Mei Zhang;Dr. Ming-Tian Zhang;Cheng Hou; Zhuo-Feng Ke; Tong-Bu Lu
Angewandte Chemie International Edition 2014 Volume 53( Issue 48) pp:13042-13048
Publication Date(Web):
DOI:10.1002/anie.201406983
Abstract
The development of an earth-abundant, first-row water oxidation catalyst that operates at neutral pH and low overpotential remains a fundamental chemical challenge. Herein, we report the first nickel-based robust homogeneous water oxidation catalyst, which can electrocatalyze water oxidation at neutral pH and low overpotential in phosphate buffer. The results of DFT calculations verify that the OO bond formation in catalytic water oxidation prefers a HOOH coupling mechanism from a cis-isomer of the catalyst.
Co-reporter:Mei Zhang;Dr. Ming-Tian Zhang;Cheng Hou; Zhuo-Feng Ke; Tong-Bu Lu
Angewandte Chemie International Edition 2014 Volume 53( Issue 48) pp:
Publication Date(Web):
DOI:10.1002/anie.201484861
Co-reporter:Yun-Nan Gong, Long Jiang and Tong-Bu Lu
Chemical Communications 2013 vol. 49(Issue 94) pp:11113-11115
Publication Date(Web):22 Oct 2013
DOI:10.1039/C3CC46530F
A dynamic fluorescent metal–organic framework has been constructed using triphenylene-2,6,10-tricarboxylate and Tb3+ as building blocks, which exhibits guest-responsive structural dynamism and selective sensing of nitroaromatic explosives.
Co-reporter:Ping Ju, Long Jiang and Tong-Bu Lu
Chemical Communications 2013 vol. 49(Issue 18) pp:1820-1822
Publication Date(Web):28 Jan 2013
DOI:10.1039/C3CC38519A
An unprecedented 3D dynamic porous metal–organic framework assembled from fivefold interlocked closed nanotubes has been constructed, which exhibits highly selective adsorption of CO2 over N2 and H2, as well as stepwise and hysteretic behaviors.
Co-reporter:Yong-Liang Huang, Yun-Nan Gong, Long Jiang and Tong-Bu Lu
Chemical Communications 2013 vol. 49(Issue 17) pp:1753-1755
Publication Date(Web):23 Jan 2013
DOI:10.1039/C3CC38730E
A porous Mg-based 3D metal–organic framework with unique nanoscale cages and two-fold interpenetrating pcu nets has been synthesized and characterized. It shows gas-uptake capacities for N2, H2, O2 and CO2 at low temperatures and selective adsorption of CO2 over O2 and N2 at room temperature.
Co-reporter:Yun-Nan Gong and Tong-Bu Lu
Chemical Communications 2013 vol. 49(Issue 70) pp:7711-7713
Publication Date(Web):22 Jul 2013
DOI:10.1039/C3CC42268B
A stable porous metal–organic framework (MOF) containing methyl viologen cations exhibits reversible photochromic, thermochromic and fluorescence changes via host–guest interactions, and can be used for fast and selective detection of oxygen by naked eye recognition of color change within five seconds.
Co-reporter:Mei Zhang, Wen-Juan Ma, Chun-Ting He, Long Jiang, and Tong-Bu Lu
Inorganic Chemistry 2013 Volume 52(Issue 9) pp:4873-4879
Publication Date(Web):April 5, 2013
DOI:10.1021/ic302435g
The design and synthesis of chemosensors for the recognition of a certain nucleoside polyphosphate among various structurally similar nucleoside polyphosphates remain a fundamental challenge. Herein, we report the new fluorescent chemosensor [Zn2L](ClO4)4 (1; L = (3,6,10,13,17,20,24,27-octaaza-1,15(2,6)-dipyridina-8,22(9,10)-dianthracenacyclooctacosaphane), which can selectively recognize adenosine polyphosphates (ATP and ADP) among various nucleoside polyphosphates, with a large fluorescence enhancement (Fmax/F0 = 70 and 80 for ATP and ADP, respectively) and strong binding affinity (K = 3.1 × 1011 M–1 for [Zn2HL(H–1ATP)2]−, 2.8 × 1011 M–1 for [Zn2L(H–1ATP)2]2–, and 1.5 × 1013 M–1 for [Zn2L(H–1ADP)2]2–) in aqueous solution at physiological pH 7.40. The structure of [Zn2L](P2O7) (2) was investigated, which shows that μ2-pyrophosphate anions alternately link [Zn2L]4+ cations to generate a 1D coordination polymer. The results of 31P NMR studies and DFT calculations reveal that the two Zn(II) ions in 1 can interact with ATP/ADP anions through coordination interactions between Zn(II) and the polyphosphate groups, and two anthracene moieties in 1 can interact with adenine groups from two ATP or ADP anions through stacking interactions to form a sandwichlike structure. These multiple recognition interactions between 1 and ATP/ADP enhance the affinity and selectivity of 1 toward ATP/ADP. Due to its highly selective and sensitive ability to detect adenosine polyphosphates, 1 was successfully applied to fluorescence imaging for ATP and ADP in living cells, demonstrating the potential utility of 1 as a fluorescent chemosensor for detecting ATP and ADP.
Co-reporter:Zi-Jian Li ; Jia Yao ; Qian Tao ; Long Jiang
Inorganic Chemistry 2013 Volume 52(Issue 20) pp:11694-11696
Publication Date(Web):October 1, 2013
DOI:10.1021/ic4021367
A pair of 2D chiral coordination polymers were constructed through the self-assembly of a chiral metal-camphor-10-sulfonate salt and a bidentate linker, which show selective inclusion of S and R enantiomers of 1-phenylethanol respectively with an enantioselectivity of 9:1.
Co-reporter:Gao-Yi Xie, Long Jiang and Tong-Bu Lu
Dalton Transactions 2013 vol. 42(Issue 39) pp:14092-14099
Publication Date(Web):02 Aug 2013
DOI:10.1039/C3DT51501J
Cryptand L (L = N[(CH2)2NHCH2(2,6-C10H6)CH2NH(CH2)2]3N) and its dinuclear metal cryptates [Zn2L](NO3)4 (1) and [Cu2L](ClO4)4 (2) have been prepared, and the binding properties of the cryptates with fumarate and its cis isomer maleate were investigated using fluorescent spectra, 1H NMR titrations and single crystal X-ray diffraction analysis for [(Cu2L)(fum)][ClO4]2 (3) (fum = fumarate). Thanks to the size and shape matching effect, the cryptates can selectively recognize fumarate at physiological pH, with an association constant almost 18-fold larger than that of maleate, forming a cradle-like cascade complex.
Co-reporter:Yan Yan, Jia-Mei Chen and Tong-Bu Lu
CrystEngComm 2013 vol. 15(Issue 33) pp:6457-6460
Publication Date(Web):16 Jul 2013
DOI:10.1039/C3CE41017J
Three acyclovir complexes including one salt with maleic acid, and two cocrystals with fumaric acid and glutaric acid, were prepared. The results of powder dissolution and in vitro skin permeation experiments revealed that both solubility and permeability of acyclovir were enhanced after the formation of cocrystals.
Co-reporter:Na Geng, Jia-Mei Chen, Zi-Jian Li, Long Jiang, and Tong-Bu Lu
Crystal Growth & Design 2013 Volume 13(Issue 8) pp:3546-3553
Publication Date(Web):July 5, 2013
DOI:10.1021/cg400518w
The cocrystals and salts of an antiallergic drug, tranilast, were synthesized to improve its solubility and photostability. Two tranilast cocrystals with urea (1) and nicotinamide (2), as well as two salts with cytosine (3) and sodium ion (4), were obtained and characterized by infrared spectra, thermogravimetric analyses, differential scanning calorimetry, and powder and single crystal X-ray diffractions. The results of single crystal structure analyses of 1–3 indicate that tranilast combines amide groups in coformers via R22(8) synthon, resulting in a 1:1 stoichiometry. The complexes showed advantages in terms of solubility and photostability in comparison to pure tranilast. The maximum solubility values of 1–3 in phosphate buffer of pH 6.8 are approximately 1.6, 1.9, and 2.0 times as large as that of tranilast, and the residual of tranilast is 79.5, 92.9, 88.5, 86.2, and 87.4% for tranilast and 1–4, respectively, under the fluorescent lamp irradiation for 96 h.
Co-reporter:Wen-Juan Ma, Jia-Mei Chen, Long Jiang, Jia Yao, and Tong-Bu Lu
Molecular Pharmaceutics 2013 Volume 10(Issue 12) pp:4698-4705
Publication Date(Web):November 4, 2013
DOI:10.1021/mp400529m
In recent years, cucurbit[7]uril (CB[7]) has attracted great attention in drug delivery. Though the effect of CB[7] in enhancing the solubility of water insoluble drugs has been validated, the underlying mechanism remains poorly understood, particularly at a molecular level. This study is designed to evaluate a CB[7]-based pharmaceutical formulation to improve solubility and bioavailability of triamterene (a mild potassium-sparing diuretic). Two polymorphs of triamterene@CB[7] were obtained, and their crystal structures were determined by single crystal X-ray diffraction. The CB[7] molecule forms a stable host–guest complex with triamterene (Ka = 1.69 ± 0.34 × 104 M–1) in aqueous solution (pH = 1.0). The results of dissolution study demonstrate that the apparent solubility value of triamterene@CB[7] complex in 0.1 M HCl is 1.6 times as large as that of triamterene, while free triamterene was released from triamterene@CB[7] complex in phosphate buffer of pH 6.8. Pharmacokinetic studies in rats reveal that the AUC0–∞ value of triamterene@CB[7] complex increases 2.8-fold compared with that of free triamterene, and t1/2 is prolonged from 1.42 to 2.61 h (P < 0.05) after oral administration. The increased solubility and oral bioavailability are attributed to the formation of a hydrophilic capsule composed of two CB[7] molecules, in which two insoluble triamterene molecules are encapsulated. These results demonstrate that triamterene@CB[7] complex is a stable and effective pharmaceutical formulation.Keywords: crystal structure; cucurbit[7]uril; pharmacokinetics; solubility; triamterene;
Co-reporter:Jiamei Chen;Tongbu Lu
Chinese Journal of Chemistry 2013 Volume 31( Issue 5) pp:635-640
Publication Date(Web):
DOI:10.1002/cjoc.201300217
Abstract
Structural information on the crystalline forms of mebendazole, an anti-parasitic drug, is limited, although three polymorphic forms of this drug have been reported. The present work investigates the structures and properties of different crystalline forms of mebendazole with a series of n-alkyl carboxylic acids, including trifluroacetic acid (1), formic acid (2), acetic acid (3), propanoic acid (4), butanoic acid (5), valeric acid (6) and hexanoic acid (7). These compounds were characterized by thermogravimetric analysis, IR spectra, as well as powder and single-crystal X-ray diffraction analysis. The R22(8) structural motif was detected in all the seven products, which was formed by a pair of NH···O/OH···N hydrogen bonds between mebendazole and carboxylic acid. Forms 3–7 were found to be neutral solvate, while in forms 1 and 2, proton transfer was observed from carboxylic acid to mebendazole.
Co-reporter:Yun-Nan Gong, Miao Meng, Di-Chang Zhong, Yong-Liang Huang, Long Jiang and Tong-Bu Lu
Chemical Communications 2012 vol. 48(Issue 98) pp:12002-12004
Publication Date(Web):05 Nov 2012
DOI:10.1039/C2CC35461F
A μ4-Cl bridged anionic sodalite-type porous metal–organic framework (Et2NH2)3[(Cu4Cl)3(TTCA)8]·26DEF was synthesized, in which Et2NH2+ can be exchanged by Li+ cations. The results of gas measurements indicate that Et2NH2+ and Li+ are beneficial for methane and hydrogen storage, respectively.
Co-reporter:Long Jiang, Xian-Rui Meng, Hua Xiang, Ping Ju, Di-Chang Zhong, and Tong-Bu Lu
Inorganic Chemistry 2012 Volume 51(Issue 3) pp:1874-1880
Publication Date(Web):January 9, 2012
DOI:10.1021/ic202168r
Three coordination polymers of [(NiL1)3(TCBA)2] (1), [(NiL2)3(TCBA)2] (2), and [(NiL3)3(TCBA)2] (3) have been constructed using azamacrocyclic Ni(II) complexes [NiL1](ClO4)2/[NiL2](ClO4)2/[NiL3](ClO4)2 and TCBA3- as building blocks (L1 = 3,10-bis(2-fluorobenzyl)-1,3,5,8,10,12-hexaazacyclotetradecane; L2 = 3,10-bis(3-fluorobenzyl)-1,3,5,8,10,12-hexaazacyclotetradecane; L3 = 3,10-bis(4-fluorobenzyl)-1,3,5,8,10,12- hexaazacyclotetradecane; TCBA3- = tri(4-carboxy-benzyl)amine). The results of X-ray diffraction analyses reveal that 1 shows a 2D Borromean structure, while 2 and 3 form 2D layer structures, and the 2D layers are further connected by the interlayer F···F interactions in 2 and C–H···F interactions in 3 to generate two 3D porous structures with 1D fluorine atoms interspersed channels. Gas sorption measurements illustrate that the desolvated 2 and 3can adsorb N2, H2, and CO2 molecules. The different structures and gas sorption properties of 1 and 2/3 are mainly induced by the different positions of F atoms in azamacrocycle ligands.
Co-reporter:Xiao-Dan Zheng, Mei Zhang, Long Jiang and Tong-Bu Lu
Dalton Transactions 2012 vol. 41(Issue 6) pp:1786-1791
Publication Date(Web):12 Dec 2011
DOI:10.1039/C1DT11825K
A novel achiral hexacarboxylic ligand L was synthesized. Spontaneous resolution occurred during the reaction of L with Eu(NO3)3 to produce a pair of enantiomers of 1a and 1b with a formula of [EuL(NO3)3(H2O)]·13H2O, which possesses 1D chiral open channels formed by triple-stranded helical chains. When heated to 60 °C, 1a releases coordinated and partial lattice H2O molecules to give a complex of [EuL(NO3)3]·4H2O (1a′), accompanied by a single-crystal-to-single-crystal transformation from 1a to 1a′, with the space group changing from P21 to P312. The dehydrated 1 can selectively adsorb water over organic solvents and exhibits reversible water adsorption upon dehydration and hydration.
Co-reporter:Jia-Mei Chen, Zi-Zhou Wang, Chuan-Bin Wu, Song Li and Tong-Bu Lu
CrystEngComm 2012 vol. 14(Issue 19) pp:6221-6229
Publication Date(Web):27 Jul 2012
DOI:10.1039/C2CE25724F
An anthelmintic drug, mebendazole, shows a very low bioavailability (less than 10%) due to its poor aqueous solubility (0.035 mg/mL at 25 °C for form C). To improve its solubility, we combined a group of dicarboxylic acids with mebendazole via liquid-assisted grinding and reaction crystallization methods, and two salts with oxalic and maleic acids, as well as two co-crystals with malonic and glutaric acids, were obtained. These novel multi-component complexes were characterized by powder X-ray diffraction, differential scanning calorimetry, thermogravimetric analyses and infrared spectra. The single-crystal structures of mebendazole-maleate salt, mebendazole-glutaric acid co-crystal, and mebendazole-monomethyl oxalate salt, in which one of the carboxyl groups of oxalic acid was esterified during the single-crystal growth in methanol, were determined. It was observed that mebendazole combines dicarboxylic acid/ester via a R22(8) hydrogen-bonding motif that involves a carbamyl benzimidazole and a carboxyl group, resulting in the 1:1 stoichiometry. The powder dissolution studies revealed that the apparent solubility of the complexes was significantly increased after the formation of co-crystals and salts.
Co-reporter:Di-Chang Zhong, Ji-Hua Deng, Xu-Zhong Luo, Tong-Bu Lu and Ke-Jun Wang
CrystEngComm 2012 vol. 14(Issue 5) pp:1538-1541
Publication Date(Web):12 Jan 2012
DOI:10.1039/C2CE06555J
A three-dimensional tetrazole-based Cd(II) metal–organic framework containing rare large Cd8 and Cd23 secondary building units has been hydrothermally prepared through in situ metal/ligand reaction, which shows an unprecedented (4,10)-connected topology net.
Co-reporter:Lin-Lin Xu, Jia-Mei Chen, Yan Yan, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 12) pp:6004-6011
Publication Date(Web):October 31, 2012
DOI:10.1021/cg3010745
An antitumor drug, 6-mercaptopurine monohydrate, has a low oral bioavailability (about 16%) due to its poor aqueous solubility. To improve its solubility, two cocrystals of 6-mercaptopurine with 4-hydroxybenzoic acid (1) and 2,4-dihydroxybenzoic acid (2), as well as two salts with piperazine in 1:1 (3) and 2:1 (4) stoichiometry, respectively, were obtained and characterized by infrared spectra, powder and single crystal X-ray diffraction. The structures of 1–4 are assembled via N–H(pyrimidine)···O(carboxyl), N–H(pyrimidine)···N(imidazole), O–H(carboxyl)···S, O–H(hydroxyl)···N(imidazole), N–H(pyrimidine)···S, O–H(carboxyl)···O(carboxyl) and N–H(piperazine)···N(imidazole) hydrogen bonds. After the formation of cocrystals and salts, the solubility of 6-mercaptopurine monohydrate is much improved, and the apparent solubility values of 1–4 in the phosphate buffer of pH 6.8 are approximately 1.6, 2.0, 14.0, and 4.2 times as large as that of 6-mercaptopurine monohydrate. Interestingly, 3 transformed to 4 at 40 °C/75% RH within one month.
Co-reporter:Ji-Hua Deng, Di-Chang Zhong, Xu-Zhong Luo, Hui-Jin Liu, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 10) pp:4861
Publication Date(Web):August 31, 2012
DOI:10.1021/cg300678h
Six cadmium(II) coordination compounds with 2-propyl-imidazole-4,5-dicarboxylate (H3PIDC), including two mononuclear complexes, [Cd(H2PIDC)2(H2O)2]·4H2O (1) and [Cd2(H2PIDC)4(H2O)4]·7H2O (2), two square tetranuclear complexes, [Cd4(HPIDC)4(H2O)8]·2H2O (3) and [Cd4(HPIDC)4(py)8]·10H2O (py = pyridine, 4), one one-dimensional chain polymer, [Cd2(H2PIDC)4(H2O)2]n·2nH2O (5), as well as one two-dimensional layer polymer, [Cd(H2PIDC)2]n (6), have been prepared using solvent evaporation method and hydrothermal method. The results of single-crystal X-ray diffraction analyses indicate that, besides the common supramolecular interactions such as hydrogen bond and π···π stacking, the hydrophobic interaction among the propyl groups in the H3PIDC ligands also contributes to the stabilities of 1–6. The study of substance transformation for 3 reveals that the coordinated H2O molecules in 3 can be well replaced by pyridine molecules, indirectly leading to the formation of 4. The results of photoluminescent measurements illustrate upon photoexcitation that 3–6 can emit fluorescence in the wavelength range of 451–473 nm in the solid state.
Co-reporter:Di-Chang Zhong, Ji-Hua Deng, Xu-Zhong Luo, Hui-Jin Liu, Jin-Lian Zhong, Ke-Jun Wang, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 4) pp:1992-1998
Publication Date(Web):February 24, 2012
DOI:10.1021/cg2016963
Two cadmium(II) metal–organic frameworks based on two mixed ligands of HBTA and H2BDC, [Cd5(BTA)6(BDC)2(DMF)4(H2O)2]n·n(2DMF·H2O) (1) and [Cd7(BTA)2(BDC)6(DMF)8]n·2nDMF (2) (HBTA = 1,2,3-benzenetriazole; H2BDC = 1,4-benzenedicarboxylic acid), have been prepared through methods of liquid to liquid diffusion and solvothermal reaction, respectively. The results of single-crystal X-ray diffraction analyses indicate that both MOFs are constructed from cadmium clusters. In 1, six BTA– anions connect five Cd(II) ions to generate a tetrahedral Cd5 cluster, which further links with four equivalent Cd5 clusters through four BDC2– bridges, forming a (4,4)-connected two–dimensional (2D) layer structure. In 2, each BTA– anion connects three Cd(II) ions to generate a triangular Cd3 cluster, which further links with four Cd3 clusters and two 3-connected BDC2– anions, forming a (3,6)-connected three-dimensional (3D) framework. The results of photoluminescent measurements illustrate that in the solid state, both 1 and 2 can emit fluorescence at 465 and 450 nm, respectively.
Co-reporter:Yan Yan, Jia-Mei Chen, Na Geng, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 5) pp:2226-2233
Publication Date(Web):March 28, 2012
DOI:10.1021/cg201423q
Four cocrystals of agomelatine with urea (1), glycolic acid (2), isonicotinamide (3), and methyl4-hydroxybenzoate (4) in 1:1 stoichiometry were successfully synthesized via six kinds of synthons. The structures of 1–4 were determined by the single crystal X-ray diffraction, in which 1–3 form two-dimensional hydrogen bonded frameworks between agomelatine and coformers, while 4 displays a one-dimensional chain structure. The results of differential scanning calorimetry measurements indicate that the melting points of 1–3 are between those of agomelatine and coformers, while the melting point of 4 is below those of agomelatine and coformer. After the formations of cocrystals, the solubility of agomelatine is much improved, and the solubility values of 1–4 in phosphate buffer of pH 6.8 are approximately 2.2, 2.9, 4.7, and 3.5 times as large as that of agomelatine Form II, and 1.6, 2.1, 3.4, and 2.5 times as large as that of agomelatine Form I. The solids of 1–4 can keep their crystalline forms in phosphate buffer of pH 6.8 for 3.5, 2.0, 6.0, and 15.0 h, respectively.
Co-reporter:Qian Tao, Jia-Mei Chen, Lei Ma, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 6) pp:3144-3152
Publication Date(Web):May 7, 2012
DOI:10.1021/cg300327x
One phenazopyridine monohydrate (1·H2O), one cocrystal of phenazopyridine with phthalimide (2), and three salts of phenazopyridine with benzoic acid (3), 4-hydroxyphenylacetic acid (4), and scaaharin (5) were synthesized, and their structures were determined by single crystal X-ray diffraction. The results of dissolution experiments indicate that the solubility of phenazopyridine can be enhanced after the formations of cocrystal and salts, in which the apparent solubility value of 5is approximately 9 times as large as that of phenazopyridine in water, and the apparent solubility value of 4 is approximately 10 times as large as that of phenazopyridine hydrochloride (1·HCl) in 0.1 M HCl aqueous solution. The results of the stability study demonstrate that 2–5 are less hygroscopic than 1·H2O and 1·HCl at both 85% and 98% RH.
Co-reporter:Wen-Guan Lu, Di-Chang Zhong, Long Jiang, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 7) pp:3675-3683
Publication Date(Web):June 12, 2012
DOI:10.1021/cg300476e
Three series of lanthanide coordination polymers of {[Ln2(HIDC)2(SO4)(H2O)5]·H2O}n (CPs-1Ln, Ln = Sm, Eu, Tb, Dy, Ho, Er, and Yb), {(H2prz)[Ln2(HIDC)2(SO4)2]}n (CPs-2Ln, Ln = Sm and Eu), and [Ln2(HIDC)2(SO4)(H2O)2]n (CPs-3Ln, Ln = Tb, Dy, Ho, Er, and Yb) have been hydrothermally synthesized by the reactions of Ln(NO3)3·6H2O with imidazole-4,5-dicarboxylic acid (H3IDC) and sulfuric acid (H2SO4) in the presence of piperazine (prz) at different temperatures. The results of the single-crystal X-ray diffraction analysis reveal that CPs-1Ln presents a three-dimensional (3D) architecture, in which alternating one-dimensional (1D) right-/left-handed helical chains of [Ln2(HIDC)2]∞ are interlinked by μ3-SO42– anions. CPs-2Ln assumes a H2prz2+ templated 3D anionic layer-pillared metal–organic framework (MOF) of {[Ln2(HIDC)2(SO4)2]}n2n–, in which two-dimensional (2D) (6,3) network layers of [Ln2(HIDC)2]n2n+ are pillared by μ2-SO42– anions. CPs-3Ln is a 2D layer structure, in which two 2D (6,3) monolayers of [Ln2(HIDC)2(H2O)2]n2n+ are connected by μ2-SO42– anions to form a 2D double-layer structure. The adjacent 2D double-layers are further stacked together via strong hydrogen bonding interactions to generate a 3D supramolecular framework. In addition, the results of photoluminescent measurements for Sm (1Sm and 2Sm), Eu (1Eu and 2Eu), Tb (1Tb and 3Tb), and Dy (1Dy and 3Dy) compounds in the solid state at room temperature indicate that different structural types have a different influence on their characteristic photoluminescences.
Co-reporter:Zi-Zhou Wang, Jia-Mei Chen, and Tong-Bu Lu
Crystal Growth & Design 2012 Volume 12(Issue 9) pp:4562-4566
Publication Date(Web):August 7, 2012
DOI:10.1021/cg300757k
Four cocrystals of (S-ox)(ga) (1), (RS-ox)(ga) (2), (S-ox)(pa) (3), and (RS-ox)(pa) (4) were prepared (S-ox = S-oxiracetam, RS-ox = racemic oxiracetam, ga = gallic acid, pa = 3,4-dihydroxybenzoic acid), and their structures were determined by single X-ray diffraction. In 1/2, two ga molecules link two S-ox/RS-ox molecules through intermolecular hydrogen bonds with a new R22(9) synthon to form a tetramer, the tetramers are further linked by intertetramer hydrogen bonds to generate a 2D sheet, and the adjacent 2D sheets are connected by intersheet hydrogen bonds to form the 3D structure of 1/2. In 3/4, the ox molecules form a 1D helical chain through intermolecular hydrogen bonds, and the helical chains are further linked by pa molecules through intermolecular hydrogen bonds to form a 2D sheet. The results of hygroscopic stability experiments indicate that the hygroscopic stability of S-ox is much enhanced after the formation of cocrystal 1.
Co-reporter:Gao-Yi Xie, Long Jiang and Tong-Bu Lu
RSC Advances 2012 vol. 2(Issue 33) pp:12728-12731
Publication Date(Web):08 Nov 2012
DOI:10.1039/C2RA22423B
A protonated azamacrocyclic chemosensor containing two anthracene fragments can recognize 1,5-naphthalenedisulfonate (1,5-NDS) over halides and other oxoanions, 1H NMR spectra and crystal structure analysis give further insight into the binding interactions.
Co-reporter:Hua Xiang, Yanhua Lan, Long Jiang, Wei-Xiong Zhang, Christopher E. Anson, Tong-Bu Lu, Annie K. Powell
Inorganic Chemistry Communications 2012 Volume 16() pp:51-54
Publication Date(Web):February 2012
DOI:10.1016/j.inoche.2011.11.029
New chiral Schiff-base ligand l-H2vap, derived from the condensation of o-vanillin and l-2-amino-3-phenyl-1-propanol, reacts with Cu(Ac)2·H2O and Gd(NO3)3·6H2O in the presence of triethylamine to produce a chiral tetranuclear complex l-[Cu4(Hvap)2(vap)2(MeOH)2](NO3)2·MeOH (1). The single-crystal X-ray diffraction analyses reveal that complex 1 crystallizes in the chiral monoclinic space group P21 with Z = 2. Four copper(II) atoms are held together by two alkoxide μ3-O2 − atoms and two phenoxide μ2-O2 − atoms from four individual ligands to form a boat-shaped {Cu4O4} unit. The solid-state CD spectra confirm the chiral nature of complex 1. Magnetic studies indicate that there are strong antiferromagnetic interactions between the adjacent copper(II) ions in complex 1.A chiral tetranuclear complex, l-[Cu4(Hvap)2(vap)2(MeOH)2](NO3)2·MeOH (1), has been synthesized and structurally characterized. The solid-state CD spectra and magnetic property of complex 1 were also investigated.Highlights► A new chiral Schiff-base ligand l-H2vap was reported. ► The synthesis, structure and CD spectra of a tetranuclear complex were investigated. ► The magnetic studies reveal strong antiferromagnetic interactions between copper(II) ions.
Co-reporter:Di-Chang Zhong, Wei-Xiong Zhang, Feng-Lei Cao, Long Jiang and Tong-Bu Lu
Chemical Communications 2011 vol. 47(Issue 4) pp:1204-1206
Publication Date(Web):25 Nov 2010
DOI:10.1039/C0CC03506H
A three-dimensional microporous metal–organic framework [Cd2(Tzc)2]n, which is dehydrated from [Cd2(Tzc)2(H2O)2]n, exhibits selective gas adsorption and large hydrogen sorption hysteresis.
Co-reporter:Huan-Yong Li ; Long Jiang ; Hua Xiang ; Trevor A. Makal ; Hong-Cai Zhou
Inorganic Chemistry 2011 Volume 50(Issue 8) pp:3177-3179
Publication Date(Web):March 24, 2011
DOI:10.1021/ic200264s
The reactions of a pair of enantiomers of macrocyclic nickel(II) complexes with racemic penicillamine generated two 3D hydrogen-bonded homochiral frameworks of {[Ni(f-(SS)-L)]2(l-pends)(ClO4)2}n (Λ-1) and {[Ni(f-(RR)-L)]2(d-pends) (ClO4)2}n (Δ-1). The frameworks possess 1D tubular pores and opposite right/left-handed helical porous surfaces (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane; pends2− = penicillaminedisulfide anion).
Co-reporter:Xiao-Dan Zheng, Yan-Long Hua, Ren-Gen Xiong, Jia-Zhen Ge, and Tong-Bu Lu
Crystal Growth & Design 2011 Volume 11(Issue 1) pp:302-310
Publication Date(Web):December 3, 2010
DOI:10.1021/cg101314j
The reaction of the chiral macrocyclic compound [Ni(SS-L)](ClO4)2 with Na2[Fe(CN)5NO] in acetonitrile/water gave {[Ni(SS-L)][cis-Fe(CN)5NO]}n (Δ-2) and {[Ni(SS-L)][trans-Fe(CN)5NO]}n (Λ-3), and the reaction of chiral [Ni(RR-L)](ClO4)2 with Na2[Fe(CN)5NO] gave the corresponding {[Ni(RR-L)][cis-Fe(CN)5NO]}n (Λ-2) and {[Ni(RR-L)][trans-Fe(CN)5NO]}n (Δ-3), while the reaction of racemic [Ni(rac-L)](ClO4)2 with Na2[Fe(CN)5NO] generated five supramolecular isomers of one achiral {[Ni(rac-L)][cis-Fe(CN)5NO]}2 (meso-1) and four homochiral Δ-2/Λ-2 and Δ-3/Λ-3 (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). In meso-1, a pair of enantiomers of [Ni(SS-L)]2+ and [Ni(RR-L)]2+ are bridged by two [Fe(CN)5NO]2− through two cis cyano groups to form a [2 + 2] type of discrete molecular square. In Δ-2/Λ-2, the homochiral [Ni(SS-L)]2+/[Ni(RR-L)]2+ cations are alternately bridged by [Fe(CN)5NO]2− anions through two cis cyano groups to produce one-dimensional (1D) homochiral right-handed and left-handed helical chains of Δ-2 and Λ-2, respectively. In Δ-3/Λ-3, however, the homochiral [Ni(RR-L)]2+/[Ni(SS-L)]2+ cations are alternately bridged by [Fe(CN)5NO]2− anions through two trans cyano groups to produce 1D homochiral right-handed and left-handed helical chains in Δ-3 and Λ-3, respectively. Their thermal stability, CD spectra, magnetic and dielectric properties were also investigated.
Co-reporter:Sai-Li Zheng, Jia-Mei Chen, Wei-Xiong Zhang, and Tong-Bu Lu
Crystal Growth & Design 2011 Volume 11(Issue 2) pp:466-471
Publication Date(Web):January 6, 2011
DOI:10.1021/cg101234p
Two polymorphic structures of Form II and Form III of agomelatine were determined by single and powder X-ray diffraction, respectively, in which the agomelatine molecules are linked through the intermolecular hydrogen bonding interactions to form a one-dimensional (1D) chain, and the 1D chains are further packed through interchain π···π and C−H···π interactions to generate the three-dimensional (3D) structures. Two agomelatine cocrystals with acetic acid (1) and ethylene glycol (2) were synthesized, and their structures were determined by single and powder X-ray diffraction, respectively, in which the acetic acid molecules in 1 alternately link the agomelatine molecules to form 1D right-handed and left-handed helical chains, while the alternately linking of agomelatine molecules by ethylene glycol molecules in 2 generates the homochiral right-handed helical chains. After the formation of cocrystals of 1 and 2, the melting points dramatically decrease, and the solubility is approximately twice as large as that of Form II.
Co-reporter:Xian-Rui Meng, Di-Chang Zhong, Long Jiang, Huan-Yong Li, and Tong-Bu Lu
Crystal Growth & Design 2011 Volume 11(Issue 5) pp:2020-2025
Publication Date(Web):April 1, 2011
DOI:10.1021/cg2002157
Two 2D metal−organic frameworks (MOFs) of [NiL1]3[BTC]2·7H2O·6DMF (1) and [NiL2]3[BTC]2·H2O·3DMF (2) have been constructed using macrocyclic Ni(II) complexes ([NiL1](ClO4)2/[NiL2](ClO4)2) and BTC3- as building blocks [L1 = 3,10-bis(4- fluorobenzyl)-1,3,5,8,10,12-hexaazacyclotetradecane, L2 = 3,10-bis(2-fluorobenzyl)-1,3,5,8,10,12-hexaazacyclotetradecane, and BTC3- = 1,3,5-benzenetricarboxylate]. The results of X-ray diffraction analyses indicate that 1 shows a 2D brick wall structure with BTC3- bridging three [NiL1]2+ via C1 symmetry, while 2 displays a 2D honeycomb-like structure with BTC3- bridging three [NiL2]2+ via C3 symmetry. The results of gas sorption measurements indicate that desolvated 1 can selectively adsorb CO2 rather than N2 and H2, while desolvated 2 cannot adsorb any of these gases under the same condition. More interestingly, the sorption isotherm of CO2 for desolvated 1 shows a large hysteresis. The different sorption properties of desolvated 1 and 2 can be attributed to their different structures tuned by the positions of the fluorine atoms in the macrocyclic ligands.
Co-reporter:Miao Meng, Di-Chang Zhong and Tong-Bu Lu
CrystEngComm 2011 vol. 13(Issue 22) pp:6794-6800
Publication Date(Web):13 Sep 2011
DOI:10.1039/C1CE05817G
Three porous metal–organic frameworks (MOFs) of {[Cd(HABTC)(H2O)2]·3H2O}n (1), {[Cd3(ABTC)2(H2O)9]·CH3OH·DMF·2H2O}n (2), and {[Mn3(ABTC)2(H2O)4]·9.5H2O}n (3) have been constructed using azobenzene-3,5,4′-tricarboxylic acid (H3ABTC) and Cd(NO3)2·4H2O/MnCl2·4H2O as building blocks. The results of single-crystal X-ray diffraction analysis indicate that 1 is a 2D layer structure with 1D open channels. 2 is a rare 3D porous structure constructed from polycatenated 2D layers. 3 also shows a 3D porous structure with 1D carboxylate bridged Mn–(COO)–Mn chains. The result of magnetic susceptibility measurements indicates that the Mn(II) ions in 3 exhibit antiferromagnetic interactions.
Co-reporter:Hua Xiang, Wen-Yang Gao, Di-Chang Zhong, Long Jiang and Tong-Bu Lu
CrystEngComm 2011 vol. 13(Issue 19) pp:5825-5832
Publication Date(Web):28 Jul 2011
DOI:10.1039/C1CE05541K
The reaction of CdCl2·1.5H2O with 1,3,5-benzenetribenzoic acid (H3BTB) in DMF gave {[Cd3(BTB)2(DMF)4]·3DMF}n (1), while the reactions of Cd(Ac)2·2H2O with H3BTB in DMF/H2O (1:10) in the presence of py, bpy, and bib generated {(Hpy)[Cd(BTB)(py)]·0.5DMF·3H2O}n (2), {Cd[Cd2(BTB)2(bpy)]·2bpy·DMF·19H2O}n (3), and {[Cd3(BTB)2(bib)3(H2O)2]·4H2O}n (4), respectively (DMF = N,N′-dimethylformamide, py = pyridine, bpy = 4,4′-bipyridine, bib = 1,4-bis(imidazol-1-yl)butane). X-Ray single-crystal analyses reveal that 1 contains a two-dimensional bilayer structure based on a carboxylate and DMF bridged Cd3 cluster. In 2, two honeycomb-like [Cd(BTB)]nn− sheets are interpenetrated with each other to form a 2D network. In 3, the 2D [Cd(BTB)]nn− honeycomb-like sheets are pillared by bpy to form a 3D framework, and the 3D frameworks are three-fold interpenetrated to generate the framework of 3 with 1D open channels, which are occupied by disordered Cd ions, bpy, DMF and water molecules. Compound 4 consists of a 3D self-penetrated framework constructed by μ2-bib bridging five-fold interpenetrated 2D bilayers. The results of gas sorption measurements indicate that the desolvated 3 can selectively adsorb CO2 and H2 over N2, with a rare large hydrogen sorption hysteresis. The luminescent properties of 1–4 were also investigated.
Co-reporter:Di-Chang Zhong, Xiao-Long Feng and Tong-Bu Lu
CrystEngComm 2011 vol. 13(Issue 7) pp:2201-2203
Publication Date(Web):15 Feb 2011
DOI:10.1039/C0CE00961J
Two µ-Cl− bridged Cd(II) organic–inorganic hybrid frameworks have been constructed with unusual I1O3 and I2O2 connectivity, respectively.
Co-reporter:Guang-Chuan Ou, Xiao-Long Feng, and Tong-Bu Lu
Crystal Growth & Design 2011 Volume 11(Issue 3) pp:851-856
Publication Date(Web):January 18, 2011
DOI:10.1021/cg101515g
The reaction of a racemic four-coordinated nickel(II) complex [Ni(α-rac-L)](ClO4)2 with l-Leu− in acetonitrile/water under basic conditions gave two six-coordinated diastereomers of {[Ni(SS-L)(l-Leu)](ClO4)}n (Δ-1) and {[Ni(RR-L)(l-Leu)](ClO4)}n (a-2). While the reaction of [Ni(α-rac-L)](ClO4)2 with d-Leu− in acetonitrile/water under basic condition generated two six-coordinated diastereomers of {[Ni(RR-L)(d-Leu)](ClO4)}n (Λ-1) and {[Ni(SS-L)(d-Leu)](ClO4)}n (b-2) (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, Leu− = leucine anion). Δ-1 and Λ-1 belong to supramolecular stereoisomers in which the [Ni(SS-L)(l-Leu)]+ and [Ni(RR-L)(d-Leu)]+ monomers are linked through the intermolecular hydrogen bonding interactions to form 1D homochiral right- and left-handed helical chains, respectively, while the connections of [{Ni(RR-L)}(l-Leu)]+/[{Ni(SS-L)}(d-Leu)]+ in a-2/b-2 through similar intermolecular hydrogen bonding interactions give 1D zigzag chains instead of 1D helical chains. In contrast, the reactions of [Ni(α-rac-L)](ClO4)2 with l/d-leucine in acetonitrile/water under acidic condition gave the left-handed helical chains of {[Ni(SS-L)(l-HLeu)](ClO4)2}n (Λ-3) and right-handed helical chains of {[Ni(RR-L)(d-HLeu)](ClO4)2}n (Δ-3), respectively, demonstrating the helicity of 1D helical chains is pH dependent The homochiral nature of Δ-1/Λ-1 and a-2/b-2 are confirmed by the results of CD spectra measurements.
Co-reporter:DiChang Zhong;TongBu Lu
Science China Chemistry 2011 Volume 54( Issue 9) pp:
Publication Date(Web):2011 September
DOI:10.1007/s11426-011-4358-z
During the last two decades, porous coordination polymers (PCPs), usually called as metal-organic frameworks (MOFs), have been developed rapidly due to their versatile structural diversities and potential physical and chemical functions. This article provides a short review of recent advances in the design and constructions of porous coordination polymers based on three planar rigid ligands, including imidazole-4,5-dicarboxlate (H3IDC), 1H-tetrazole (HTz), as well as 1H-tetrazole-5-carboxylate (H2Tzc). Their preparations, crystal structures, and desirable properties have been reviewed.
Co-reporter:Di-Chang Zhong, Miao Meng, Jie Zhu, Guo-Yu Yang and Tong-Bu Lu
Chemical Communications 2010 vol. 46(Issue 24) pp:4354-4356
Publication Date(Web):12 May 2010
DOI:10.1039/C000676A
An unprecedented organic–inorganic hybrid material with 3D inorganic and 3D organic connectivity has been constructed based on Cd(II) and tetrazolate-5-carboxylate, which shows a highly connected trinodal (4,8,16-c) topological net and SHG activity.
Co-reporter:Xiao-Dan Zheng and Tong-Bu Lu
CrystEngComm 2010 vol. 12(Issue 2) pp:324-336
Publication Date(Web):02 Oct 2009
DOI:10.1039/B911991D
Helicity and chirality are essential elements of life. Many important biopolymers such as DNA and peptides possess right-handed helical structures, while the building blocks for the constructions of such biopolymers are D-ribose and L-amino acids, respectively. For better realizing the origin of the helicity of biopolymers, a tremendous expansion in research efforts has been devoted to the design of metal complexes exhibiting helical architectures in inorganic and coordination chemistry. However, to control the chirality and helicity of the entire structures at the supramolecular level is one of the major challenges in the design and synthesis of helical structures. In this highlight, we present the general approaches for the construction of helical coordination compounds, together with a few instances illustrating the correlation between the chirality of building blocks and the helicity of 1D chains, as well as the chirality transfer among the helices.
Co-reporter:Guang-Chuan Ou, Zi-Zhou Wang, Li-Zi Yang, Cun-Yuan Zhao and Tong-Bu Lu
Dalton Transactions 2010 vol. 39(Issue 18) pp:4274-4279
Publication Date(Web):24 Mar 2010
DOI:10.1039/B921141A
The enantiopure agents d- and l-leucine, selectively bind RR and SS enantiomers from a racemate [Ni(α-rac-L)]2+ to give {[Ni(RR-L)(d-HLeu)](ClO4)2}n (Δ-1) and {[Ni(SS-L)(l-HLeu)](ClO4)2}n (Λ-1), respectively, and leave the corresponding uninteracted SS and RR enantiomers of [Ni(α-SS-L)](ClO4)2 (S-2) and [Ni(α-RR-L)](ClO4)2 (R-2). Occasionally, a few crystals of {[Ni(RR-L)(l-HLeu)](ClO4)2}n (Δ-3) and {[Ni(SS-L)(d-HLeu)](ClO4)2}n (Λ-3) were found to have accreted with the crystals of Λ-1/R-2, and Δ-1/S-2, respectively (the yields are less than 2%). The results of X-ray crystal structural analysis reveal that Δ-1 and Λ-1, S-2 and R-2, and Δ-3 and Λ-3 are enantiomers, in which Δ-1 and Δ-3 possess 1D right-handed helical chains, while Λ-1 and Λ-3 exhibit a motif of 1D left-handed helical chains. The results of DFT calculations reveal that the single-point energies of [Ni(RR-L)(d-HLeu)]2+/[Ni(SS-L)(l-HLeu)]2+ in Δ-1/Λ-1 are 582 kJ mol−1 lower than those of [Ni(RR-L)(l-HLeu)]2+/[Ni(SS-L)(d-HLeu)]2+ in Δ-3/Λ-3, demonstrating the favorable stereo-coordination environments of [Ni(α-RR-L)]2+ and [Ni(α-SS-L)]2+ towards d and l-HLeu, respectively.
Co-reporter:Di-Chang Zhong, Wen-Guan Lu, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Crystal Growth & Design 2010 Volume 10(Issue 2) pp:739
Publication Date(Web):November 24, 2009
DOI:10.1021/cg901128k
Three tetrazole-based coordination polymers, [Zn3(Tz)6(H2O)2]n (1), [Cu2(Tz)3(OH)]n (2), and {[Cu5(Tz)9](NO3)·8H2O}n (3) (Tz = tetrazolate) have been prepared under hydro(solvo)thermal conditions using ethyl tetrazolate-5-carboxylate and corresponding metal salts as building blocks, in which tetrazolate was generated via in situ decarboxylation. The results of X-ray single diffraction analyses indicate that 1 possesses a 2D layer structure with μ2-Tz− bridged six- and four-coordinated Zn(II), forming a rare kagomé dual topological layer. Compound 2 is a 3D layer−pillar structure, in which the Cu(II) ions are bridged by μ3-Tz− anions to generate a 2D sheet, and the 2D sheets are further pillared by μ2-Tz− and μ2-OH− to form a 3D framework with a fsc topology net. Compound 3 is a 3D porous framework with an acs topology net. Compound 1 exhibits photoluminescent properties with an emission peak at 467 nm, and compound 3 shows selective H2 and CO2 over N2 adsorption.
Co-reporter:Hua Xiang, Yanhua Lan, Huan-Yong Li, Long Jiang, Tong-Bu Lu, Christopher E. Anson and Annie K. Powell
Dalton Transactions 2010 vol. 39(Issue 20) pp:4737-4739
Publication Date(Web):02 Mar 2010
DOI:10.1039/C000008F
Isostructural CoII2CoIII4LnIII4 (Ln = Y (1), Gd (2) and Dy (3)) coordination clusters formed using the ligand Tris are the first examples of 3d-4f complexes involving this ligand and show weak ferromagnetic coupling between the CoII ions and slow relaxation (SMM) behaviour for 3.
Co-reporter:Wen-Guan Lu, Long Jiang, and Tong-Bu Lu
Crystal Growth & Design 2010 Volume 10(Issue 10) pp:4310-4318
Publication Date(Web):September 13, 2010
DOI:10.1021/cg100196j
Three series of two-dimensional (2D) lanthanide coordination polymers of [Ln(HIDC)(OX)0.5(H2O)2]n·(H2O)n (1Ln) (Ln = Pr and Nd), [Ln(HIDC)(OX)0.5(H2O)2]n·(H2O)n (2Ln) (Ln = Eu and Tb), and [Ln(HIDC)(OX)0.5(H2O)]n (3Ln) (Ln = Pr, Nd, Eu, and Tb) have been prepared by reacting Ln(NO3)3·6H2O with imidazole-4,5-dicarboxylic acid (H3IDC) and oxalic acid (H2OX) at different temperatures under hydrothermal conditions. The results of structural analyses indicate that 1Ln and 2Ln are supramolecular isomers, in which 1Ln displays a 2D monolayer structure of [Ln(HIDC)(OX)0.5(H2O)2]n with a (4.52)(4.53.72) topology network, while 2Ln shows a different 2D monolayer structure containing alternating one-dimensional (1D) left-handed and right-handed helical chains of [Ln(HIDC)]∞ bridged by OX2−. 3Ln has a 2D double-layer structure consisting of oxalate pillared [Ln(HIDC)(H2O)]nn+ layers. The effect of lanthanide contraction and of temperature on the structures of 1Ln-3Ln was investigated. The structure related luminescent properties of 2Eu and 3Eu, as well as 2Tb and 3Tb, were also examined.
Co-reporter:Hong-Guo Hao;Xiao-Dan Zheng ; Tong-Bu Lu
Angewandte Chemie International Edition 2010 Volume 49( Issue 44) pp:8148-8151
Publication Date(Web):
DOI:10.1002/anie.201004928
Co-reporter:Hong-Guo Hao;Xiao-Dan Zheng ; Tong-Bu Lu
Angewandte Chemie 2010 Volume 122( Issue 44) pp:8324-8327
Publication Date(Web):
DOI:10.1002/ange.201004928
Co-reporter:Di-Chang Zhong, Jian-Bin Lin, Wen-Guan Lu, Long Jiang and Tong-Bu Lu
Inorganic Chemistry 2009 Volume 48(Issue 18) pp:8656-8658
Publication Date(Web):August 24, 2009
DOI:10.1021/ic900968d
A 3D microporous cadmium(II) metal−organic framework based on 1H-tetrazole exhibits strong hydrogen binding with an initial enthalpy of adsorption of 13.3 kJ/mol, due to the smaller pore sizes and the high hydrogen binding affinity of the tetrazolyl-ring-decorated inner surface of the pores.
Co-reporter:Wen-Guan Lu, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Inorganic Chemistry 2009 Volume 48(Issue 15) pp:6997-6999
Publication Date(Web):July 1, 2009
DOI:10.1021/ic900506z
Three 3D lanthanide anionic metal−organic frameworks {K5[Ln5(IDC)4(ox)4]}n·(20H2O)n with 1D channels were synthesized under hydrothermal conditions [Ln = Gd (1), Tb (2), and Dy (3)]. The K+ ions within the 1D channel are easily exchanged with various cations. The emission intensities of TbIII in 2 increased significantly upon the addition of Ca2+ ions, while the introduction of other metal ions caused the intensities to be either unchanged or weakened.
Co-reporter:Li-Zi Yang, Yu Li, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
CrystEngComm 2009 vol. 11(Issue 11) pp:2375-2380
Publication Date(Web):24 Jul 2009
DOI:10.1039/B904838C
The protonated cryptand L shows both size and temperature dependent encapsulation for tetrahedral ClO4− and H2PO4− anions (L = N[(CH2)2NHCH2(C6H4-p)CH2NH(CH2)2]3N). The crystal structures of perchlorate complex [(H6L)(ClO4)][ClO4]5(H2O)7(CH3CN) (1) and phosphate complex [(H8L)(H2O)3][H2PO4]8(H2O)9 (2) showed that the smaller ClO4− can facilely enter into the cavity of H6L6+, while the larger H2PO4− can not be encapsulated inside the cavity of H6L6+ and H8L8+ at room temperature. Upon heating, however, H2PO4− can be encapsulated into the cavity of H8L8+ to generate a complex of [(H8L)(H2PO4)][H2PO4]7(H2O)18 (3), and the encapsulated H2PO4− can be released by increasing the pH value to 2.
Co-reporter:Xiao-Dan Zheng, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Dalton Transactions 2009 (Issue 34) pp:6802-6808
Publication Date(Web):07 Jul 2009
DOI:10.1039/B904081A
The reactions of [Ni(α-SS-L)](ClO4)2/[Ni(α-RR-L)](ClO4)2 with dca− gave two enantiomers of [Ni(SS-L)](dca)2 (S-1) and [Ni(RR-L)](dca)2 (R-1) in acetonitrile/water, and two supramolecular stereoisomers of {[Ni(SS-L)]2(dca)3(ClO4)·DMF}n (Δ-2) and {[Ni(RR-L)]2(dca)3(ClO4)·DMF}n (Λ-2) in acetonitrile/DMF, respectively (L = 5,5,7,12,12, 14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, dca = dicyanamide, N(CN)2−). While the reaction of racemic [Ni(α-rac-L)](ClO4)2 (containing an equal amount of SS and RR enantiomers) with dca− in acetonitrile/water or acetonitrile/DMF produced a trimer of [Ni(rac-L)(dca)]3·(dca)·(ClO4)2·MeCN (3) rather than S-1/R-1 or Δ-2/Λ-2. X-ray single-crystal analysis reveals that S-1/R-1 and Δ-2/Λ-2 crystallize in a chiral space groupP21, while 3 crystallizes in a centrosymmetric space groupC2/c. In S-1/R-1, the [Ni(SS-L)](dca)2/[Ni(RR-L)](dca)2 monomers are linked through intermolecular hydrogen bonds to form a two-dimensional sheet. While the intermolecular hydrogen bonding linking of {[Ni(SS-L)]2(dca)3}+/{[Ni(RR-L)]2(dca)3}+ leads to the formation of a 1D right-handed helical chain of Δ-2 and 1D left-handed helical chain of Λ-2, respectively, demonstrating there is a correlation between the helicity of 1D chains and the chirality of building blocks. Complex 3 forms a triangular structure of {[Ni(rac-L)(dca)]3}3+, in which the macrocyclic ligand L adopts unsymmetrical RR/RR/SS or RR/SS/SS configurations. The homochiral nature of S-1/R-1 and Δ-2/Λ-2 are confirmed by the results of solid circular dichroism (CD) spectra measurements. The magnetic properties of chiral Δ-2/Λ-2 and achiral 3 were investigated.
Co-reporter:Guang-Chuan Ou, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Dalton Transactions 2009 (Issue 1) pp:71-76
Publication Date(Web):18 Nov 2008
DOI:10.1039/B810802A
The reactions of four-coordinated transition metal macrocyclic complexes [ML](ClO4)2 (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, M = Ni, Cu) with NH4VO3 under different conditions gave four coordination polymers of {[(CuL)0.5(H2L)1.5][H2V10O28]·6H2O}n (1·6H2O), {[NiL]3[V16O38(H2O)]·6H2O}n (2·6H2O), {[NiL][VO3]2·0.33H2O}n (3·0.33H2O), and {[CuL][VO3]2·0.33H2O}n (4·0.33H2O). Single crystal X-ray diffraction analyses reveal that four diverse vanadium polyoxoanions, [H2V10O28]4−cluster, [V16O38(H2O)]6− cage, [V6O18]6− ring, and [VO3]nn− chain, were obtained from the same reactant NH4VO3 under different conditions. In 1, the cluster anion [H2V10O28]4− alternately bridges [CuL]2+/[H2L]2+ to form a one-dimensional chain, and the [V16O38(H2O)]6− cage in 2 links three [NiL]2+ into a two-dimensional sheet. Compounds 3 and 4 show three-dimensional structures, which are constructed by the connections of hexanuclear [V6O18]6− rings with [NiL]2+ in 3, and [VO3]nn− chains with [CuL]2+ in 4, respectively, generating one-dimensional channels occupied by guest water molecules.
Co-reporter:Hua Xiang;Shao-Jun Wang;Long Jiang;Xiao-Long Feng
European Journal of Inorganic Chemistry 2009 Volume 2009( Issue 14) pp:2074-2082
Publication Date(Web):
DOI:10.1002/ejic.200801170
Abstract
A series of cyanido-bridged complexes {[FeIII(phen) (CN)4]2[NiL1]}·4H2O (1), {[FeIII(bipy)(CN)4]2[NiL1]}·4H2O (2), [FeIII(bipy)(CN)4]2[NiL2] (3), {[FeIII(phen)(CN)4]2[CuL3]}·5H2O (4), {[FeII(phen)(CN)4][Ni(ea)2]}2·2H2O (5), {[FeII(phen)(CN)4] [NiL2]·2H2O}n (6), {[FeIII(bipy)(CN)4]2[Ni(H2O)2]}·6.5H2O}n (7) and {[FeII(bipy)(CN)4][Ni(ea)2]·H2O}n (8) were synthesized using H[Fe(phen)(CN)4]·2H2O and H[Fe(bipy)(CN)4]·2H2O as precursors [L1 = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, L2 = 3,10-bis(2-phenylethyl)-1,3,5,8, 10,12-hexaazacyclotetradecane, L3 = 3,10-bis(2-hydroxyethyl)-1,3,5,8,10,12-hexaazacyclotetradecane, phen = 1,10-phenanthroline, bipy = 2,2′-bipyridine, ea = ethanolamine). Complexes 1–4 are trinuclear clusters, and 5 is a tetranuclear square. In 6, the [FeII(phen)(CN)4]2– anions alternately bridge the [NiL2]2+ cations to generate a 1D wavy chain. The structure of 7 possesses a 4,2-ribbonlike chain, which contains a NiII2(CN)4FeIII2 square with each NiII atom shared by two adjacent squares. Each FeII and NiII atom in 8 acts as a three-connected node through the cyanido-bridges to generate a 2D network with a 4,82 topological net. Ferromagnetic couplings are found between the low-spin FeIII ions and the NiII ions through the cyanido groups in 1–3 and 7, and a metamagnetic behavior and a frequency dependence of the out-of-phase ac susceptibility are observed in 7. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Co-reporter:Wen-Guan Lu, Kang Yang, Long Jiang, Xiao-Long Feng, Tong-Bu Lu
Inorganica Chimica Acta 2009 Volume 362(Issue 15) pp:5259-5264
Publication Date(Web):1 December 2009
DOI:10.1016/j.ica.2009.10.001
Co-reporter:Li-Zi Yang;Yu Li;Xiao-Mei Zhuang;Long Jiang;Jia-Mei Chen;RudyL. Luck
Chemistry - A European Journal 2009 Volume 15( Issue 45) pp:12399-12407
Publication Date(Web):
DOI:10.1002/chem.200901610
Abstract
We previously reported that dinuclear copper(II) cryptate [Cu2L]4+ cleaves the CC bond of acetonitrile at room temperature to produce a cyano-bridged dinuclear cryptate and methanol, whereby the reaction mechanism has not yet become clear. We have now systemically investigated this reaction, and four cryptates, [Cu2L](ClO4)4 (1), [Zn2L](ClO4)4 (2), [Cu2L(H2O)2](CF3SO3)4 (5), and [Cu2L(OH)(OH2)](ClO4)3 (6) are reported here. Cryptates 1 and 2 can cleave the CC bonds of acetonitrile, propionitrile, and benzonitrile at room temperature under open atmospheric conditions to give cyano-bridged cryptates [Cu2L(CN)](ClO4)3 (3) and [Zn2L(CN)](ClO4)3 (4), respectively, and the corresponding alcohol. In contrast, 5 and 6 do not show any CC bond activation of nitriles, as the interior axial positions of CuII in 5 and 6 are occupied by water/OH−. The CC bond cleavage of (S)-(+)-2-methylbutyronitrile by 2 produced (R)-(−)-2-butanol only; that is, the cleavage reaction proceeds through an SN2 pathway (Walden inversion).
Co-reporter:GuangChuan Ou;Long Jiang;XiaoLong Feng;TongBu Lu
Science China Chemistry 2009 Volume 52( Issue 4) pp:465-470
Publication Date(Web):2009 April
DOI:10.1007/s11426-009-0043-x
Two supramolecular complexes, [Ni(rac-L)]3[CrO4]2[ClO4]2·4H2O (1) and [meso-H2L]0.5[VO3]·0.16H2O (2) (L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetra-decane), have been prepared in an aqueous solution, and detected by elemental analysis, IR, TG, and single crystal X-ray diffraction analyses. Compound 1 shows a one-dimensional hexagonal prism formed by the hydrogen bonding interactions between the secondary amines of rac-L and CrO42 anion/water molecules. Compound 2 displays a three-dimensional structure constructed by the hydrogen bond linking the helical chains of [VO3]nn− to the secondary amines of meso-L to generate 1D hexagon-shaped channels, and the channels are occupied by guest water molecules.
Co-reporter:Guang-Chuan Ou ; Long Jiang ; Xiao-Long Feng
Inorganic Chemistry 2008 Volume 47(Issue 7) pp:2710-2718
Publication Date(Web):February 15, 2008
DOI:10.1021/ic7021424
The reactions of a racemic four-coordinated nickel(II) complex [Ni(α-rac-L)](ClO4)2 (containing equal amount of SS and RR enantiomers) with l- and d-phenylalanine in acetonitrile/water gave two less-soluble six-coordinated enantiomers of {[Ni(f-SS-L)(l-Phe)](ClO4)}n (Δ-1) and {[Ni(f-RR-L)(d-Phe)](ClO4)}n (Λ-1), respectively. Evaporation the remaining solutions gave two six-coordinated diastereomers of {[Ni3(f-RR-L)3(l-Phe)2(H2O)](ClO4)4}n (a-2) and {[Ni3(f-SS-L)3(d-Phe)2(H2O)](ClO4)4}n (b-2), respectively (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, Phe− = phenylalanine anion). The reaction of [Ni(α-rac-L)](ClO4)2 with dl-Phe− gave a conglomerate of c-1; in which, the SS and RR enantiomers preferentially coordinate to l- and d-Phe− respectively to give a racemic mixture of Δ-1 and Λ-1, and the spontaneous resolution occurs during the reaction, in which each crystal crystallizes to become enantiopure. Removing Phe− from Δ-1 and Λ-1 using perchloric acid gave two enantiomers of [Ni(α-SS-L)](ClO4)2 (S-3) and [Ni(α-RR-L)](ClO4)2 (R-3). Dissolving S-3 and R-3 in acetonitrile gave two six-coordinated enantiomers of [Ni(f-SS-L)(CH3CN)2](ClO4)2 (S-4) and [Ni(f-RR-L)(CH3CN)2](ClO4)2 (R-4), while dissolving [Ni(α-rac-L)](ClO4)2 in acetonitrile gave a racemic twining complex [Ni(f-rac-L)(CH3CN)2](ClO4)2 (rac-4). Δ-1 and Λ-1 belong to supramolecular stereoisomers, which are constructed via hydrogen bond linking of [Ni(f-SS-L)(l-Phe)]+ and [Ni(f-RR-L)(d-Phe)]+ monomers to form 1D homochiral right-handed and left-handed helical chains, respectively. The reaction of S-3 with d-Phe− gave {[Ni(f-SS-L)(d-Phe)](ClO4)}n (5), which shows a motif of a 1D hydrogen bonded zigzag chain instead of a 1D helical chain. Compound a-2/b-2 contains dimers of [{Ni(f-RR-L)}2(l-Phe)(H2O)]3+/[{Ni(f-SS-L)}2(d-Phe)(H2O)]3+ and 1D zigzag chains of {[Ni(f-RR-L)(l-Phe)]+}n/{[Ni(f-SS-L)(d-Phe)]+}n. The homochiral nature of Δ-1/Λ-1, a-2/b-2, S-3/R-3, and S-4/R-4 are confirmed by the results of circular dichroism (CD) spectra measurements.
Co-reporter:Jia-Mei Chen ; Xiao-Mei Zhuang ; Li-Zi Yang ; Long Jiang ; Xiao-Long Feng
Inorganic Chemistry 2008 Volume 47(Issue 8) pp:3158-3165
Publication Date(Web):March 5, 2008
DOI:10.1021/ic702143d
The crystal structures of [Co2L(Cl)](ClO4)3 (1), [Co2L(Br)](ClO4)3 (2), [Co2L(OH)(OH2)]I3 (3), and [Co2L1(Cl)](ClO4)3 (4), the density functional theory calculations, as well as the binding constants of [Co2L]4+ toward Cl− and Br− and of [Co2L1]4+ toward Cl−, are reported in this paper (L = N[(CH2)2NHCH2(C6H4-p)CH2NH(CH2)2]3N, L1 = N[(CH2)2NHCH2(C6H4-m)CH2NH(CH2)2]3N). The rigid dicobalt(II) cryptate [Co2L]4+ shows the recognition of Cl− and Br− but not of F− and I−, because of the size matching to its rigid cavity. We also found that the relative rigid tripodal skeleton of L than that of L1 results in the higher affinity of [Co2L]4+ toward Cl−. Magnetic susceptibility measurements of 1 and 2 indicate that the two Co(II) atoms in the cryptates are antiferromagnetically coupled through the Cl−/Br− bridge, with g = 2.19, J = −13.7 cm−1 for 1, and g = 2.22, J = −17.1 cm−1 for 2.
Co-reporter:Xiao-Dan Zheng ; Long Jiang ; Xiao-Long Feng
Inorganic Chemistry 2008 Volume 47(Issue 23) pp:10858-10865
Publication Date(Web):October 28, 2008
DOI:10.1021/ic8009578
The reactions of racemic and enantiopure macrocyclic compounds [Ni(α-rac-L)](ClO4)2 (containing equal amounts of SS and RR enantiomers), [Ni(α-SS-L)](ClO4)2, and [Ni(α-RR-L)](ClO4)2 with K[Ag(CN)2] in acetonitrile/water afford three 1D helical chains of {[Ni(f-rac-L)][Ag(CN)2]2}n (1), {[Ni(f-SS-L)]2[Ag(CN)2]4}n (Δ-2), and {[Ni(f-RR-L)]2[Ag(CN)2]4}n (Λ-2); one dimer of [Ni(f-rac-L)][Ag(CN)2]2 (3); and one trimer of [Ni(f-rac-L)Ag(CN)2]3·(ClO4)3 (4) (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). Compounds 1, Δ-2, Λ-2, and 3, which are supramolecular isomers, are constructed via argentophilic interactions. In 1, [Ni(f-RR-L)][Ag(CN)2]2 enantiomers alternately connect with [Ni(f-SS-L)][Ag(CN)2]2 enantiomers through intermolecular argentophilic interactions to form a 1D meso-helical chain, and the 1D chains are further connected through the interchain hydrogen bonds to generate a 2D network. When chiral [Ni(α-SS-L)](ClO4)2 and [Ni(α-RR-L)](ClO4)2 were used as building blocks, two supramolecular stereoisomers of Δ-2 and Λ-2 were obtained, which show the motif of homochiral right-handed and left-handed helical chains, respectively, and the 1D homochiral helical chains are linked by the interchain hydrogen bonds to form a 3D structure. In 3, a pair of enantiomers of [Ni(f-RR-L)][Ag(CN)2]2 and [Ni(f-SS-L)][Ag(CN)2]2 connect with each other through intermolecular argentophilic interactions to form a dimer. The reaction of [Ni(α-rac-L)](ClO4)2 with K[Ag(CN)2] in acetonitrile gives a trimer of 4; each trimer is chiral with unsymmetrical RR, RR, and SS, or RR, SS, and SS configurations. The homochiral nature of Δ-2 and Λ-2 was confirmed by the results of solid circular dichroism spectra measurements. The solid samples of 1−4 show strong fluorescent emissions at room temperature.
Co-reporter:Wen-Guan Lu, Jin-Zhong Gu, Long Jiang, Min-Yu Tan and Tong-Bu Lu
Crystal Growth & Design 2008 Volume 8(Issue 1) pp:192
Publication Date(Web):December 7, 2007
DOI:10.1021/cg060778h
Four achiral two-dimensional (2D) coordination polymers of [M(HIDC)(H2O)(prz)0.5]n (M = Fe, 1; Mn, 2; Cd, 3) and [Co(HIDC)(H2O)(pyz)0.5]n (4), one chiral 2D coordination polymer of [Mn(HIDC)(H2O)]n (5), and one 2D coordination polymer of [Fe(HIDC)(H2O)]n (6) (H3IDC = imidazole-4,5-dicarboxylic acid, prz = piperazine, pyz = pyrazine) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. In 1–3, the HIDC2− anions alternately bridge the M(II) cations to form a one-dimensional (1D) infinite helical chain of [M(HIDC)]∞ along the 21 axis. The chirality of the original formed helical chain is transferred oppositely to neighboring helical chains through the parallel coordination interactions of prz molecules between two adjacent chains, resulting in an achiral 2D sheet of [M(HIDC)(H2O)(prz)0.5]n, in which the helical chains are packed in an alternating left- and right-handed chirality. A similar achiral 2D coordination polymer of 4 was obtained when pyz was used as a linker. Compound 5 crystallizes in a chiral space group P21. In 5, the HIDC2− anions also alternately bridge the Mn(II) to form a 1D right-handed helical chain of [MnHIDC]∞ along the 21 axis, and the right-handed chirality of [MnHIDC]∞ is transferred to neighboring helical chains through the zigzag interchain coordination interactions, leading to the formation of a homochiral 2D sheet, in which all the helical chains are packed in right-handed chirality. In addition, the bulk crystallization of 5 is enantiomeric excess rather than racemic, as evidenced by the results of solid-state vibrational circular dichroism (VCD) and CD spectroscopy. In the 2D structure of 6, the HIDC2− anions alternately bridge the Fe(II) to form a 1D zigzag chain of [FeHIDC]∞ instead of a 1D helical chain, in which all the HIDC2− anions locate on the same side within the chain. Compound 3 displays strong blue fluorescent emission at room temperature. Magnetic susceptibility measurements of 2 and 5 exhibit antiferromagnetic interactions between the nearest Mn(II) within the sheet, with J = −0.48 cm−1, g = 2.10 for 2, and J = −0.51 cm−1, g = 2.03 for 5.
Co-reporter:Wen-Guan Lu, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Crystal Growth & Design 2008 Volume 8(Issue 3) pp:986
Publication Date(Web):January 11, 2008
DOI:10.1021/cg700979r
Hydrothermal reactions of imidazole-4,5-dicarboxylic acid (H3IDC), 4,4′-bipyridine (bpy), and Cd(NO3)2·4H2O under different conditions yielded four novel three-dimensional (3D) porous metal−organic frameworks (MOFs) of {[Cd5(IDC)2(HIDC)(bpy)3(py)2(H2O)3]·2NO3·2H2O}n (1), [Cd5(HIDC)2(IDC)2(py)2]n (2), {[Cd5(IDC)3(bpy)2(H2O)2]·NO3·3.5H2O}n (3), and {[KCd4(IDC)2.5(bpy)2(H2O)2]·1.5NO3·3H2O}n (4). X-ray single-crystal structural analyses revealed that IDC3− and HIDC2− in 1–4 exhibit six different types of coordination modes, among them two modes are first reported in this presentation. In 1 and 4, the cadmium ions are interconnected by μ5-IDC3− in two different asymmetrical coordination modes to produce two different infinite two-dimensional (2D) layers, which are further pillared by μ2-bpy (in 1) or μ5-IDC3− and μ2-bpy alternately (in 4) to form 3D porous MOFs of 1 and 4, in which the two asymmetrical coordination modes of μ5-IDC3− have not been reported. In 2 and 3, the cadmium ions are interconnected by μ5-IDC3− in a symmetrical coordination mode to form similar infinite 2D layers, and the 2D layers are further pillared by μ4-HIDC2− (in 2) or μ4-IDC3− and μ2-bpy alternately (in 3) to form 3D porous MOFs of 2 and 3. There are two different sizes of pores in 3 and 4, while the porous sizes are uniform in 1 and 2. Compounds 1, 2, and 4 display blue fluorescent emissions in the solid state at room temperature.
Co-reporter:Yu Li, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Crystal Growth & Design 2008 Volume 8(Issue 10) pp:3689-3694
Publication Date(Web):August 20, 2008
DOI:10.1021/cg800292e
A series of water clusters encapsulated inside a cryptand cavity were obtained in the cryptand-acid supramolecular adducts of [(H2O)2⊂(H6L)][H2PO4]6(H2O)3 (1·3H2O), [(H2O)3⊂(H6L)][H2PO4]6(H2O)11 (2·11H2O), [(H2O)3⊂(H6L)][CH3(C6H4-p)SO3]6(H2O)4 (3·4H2O), and [(H2O)6⊂(H6L)][SO4]3(H2O)13 (4·13H2O) (L = N[(CH2)2NHCH2(C6H4-p)CH2NH(CH2)2]3N). In 1 and 2, H6L6+ is hydrogen bonded to six H2PO4− through its protonated nitrogen atoms to form two (O···H−N−H···)3 rings at two poles of H6L6+. A well encapsulated water dimer, and a circle- and cage-shaped trimer of [H2PO4]3 are formed in 1. A well encapsulated circular water trimer and a bowl-shaped trimer of [H2PO4]3 are formed in 2. In 3, the steric effect of the tolyl group of [CH3(C6H4-p)SO3]− causes a change in the conformation of H6L6+ to generate a favorable environment for a linear water trimer inside the crystand cavity. In 4, H6L6+ bonds three SO42− anions through the protonated nitrogen atoms at the one pole, and a quasi-prismatic hexamer water cluster is formed inside the cryptand cavity.
Co-reporter:Jin-Zhong Gu, Long Jiang, Min-Yu Tan, Tong-Bu Lu
Journal of Molecular Structure (12 November 2008) Volume 890(Issues 1–3) pp:
Publication Date(Web):12 November 2008
DOI:10.1016/j.molstruc.2007.12.003
Using [(Tp)Fe(CN)3]− (Tp = hydrotris(pyrazolyl)borate) as a building block, four trinuclear complexes [MII(DMSO)4][(Tp)Fe(CN)3]2 (MII = Co, 1; Ni, 2; Mn, 3; Cu, 4) (DMSO = dimethyl sulfoxide) have been prepared and their structures and magnetic properties have been studied. Complexes 1–4 are isostructural and crystallize, in which each MII ion is coordinated by two [(Tp)Fe(CN)3]− moieties through cyano-bridges in trans positions, resulting in a linear trinuclear structure. The magnetic properties of 1–4 have been investigated in the 2–300 K temperature range. Ferromagnetic coupling occurs in cyano-bridged NiII–NC–FeIII, MnII–NC–FeIII and CuII–NC–FeIII while antiferromagnetic exchange is present between CoII and FeIII ions. The correlations between the structures and the J values are discussed.
Co-reporter:Hua Xiang, Yanhua Lan, Huan-Yong Li, Long Jiang, Tong-Bu Lu, Christopher E. Anson and Annie K. Powell
Dalton Transactions 2010 - vol. 39(Issue 20) pp:NaN4739-4739
Publication Date(Web):2010/03/02
DOI:10.1039/C000008F
Isostructural CoII2CoIII4LnIII4 (Ln = Y (1), Gd (2) and Dy (3)) coordination clusters formed using the ligand Tris are the first examples of 3d-4f complexes involving this ligand and show weak ferromagnetic coupling between the CoII ions and slow relaxation (SMM) behaviour for 3.
Co-reporter:Xiao-Dan Zheng, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Dalton Transactions 2009(Issue 34) pp:NaN6808-6808
Publication Date(Web):2009/07/07
DOI:10.1039/B904081A
The reactions of [Ni(α-SS-L)](ClO4)2/[Ni(α-RR-L)](ClO4)2 with dca− gave two enantiomers of [Ni(SS-L)](dca)2 (S-1) and [Ni(RR-L)](dca)2 (R-1) in acetonitrile/water, and two supramolecular stereoisomers of {[Ni(SS-L)]2(dca)3(ClO4)·DMF}n (Δ-2) and {[Ni(RR-L)]2(dca)3(ClO4)·DMF}n (Λ-2) in acetonitrile/DMF, respectively (L = 5,5,7,12,12, 14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, dca = dicyanamide, N(CN)2−). While the reaction of racemic [Ni(α-rac-L)](ClO4)2 (containing an equal amount of SS and RR enantiomers) with dca− in acetonitrile/water or acetonitrile/DMF produced a trimer of [Ni(rac-L)(dca)]3·(dca)·(ClO4)2·MeCN (3) rather than S-1/R-1 or Δ-2/Λ-2. X-ray single-crystal analysis reveals that S-1/R-1 and Δ-2/Λ-2 crystallize in a chiral space groupP21, while 3 crystallizes in a centrosymmetric space groupC2/c. In S-1/R-1, the [Ni(SS-L)](dca)2/[Ni(RR-L)](dca)2 monomers are linked through intermolecular hydrogen bonds to form a two-dimensional sheet. While the intermolecular hydrogen bonding linking of {[Ni(SS-L)]2(dca)3}+/{[Ni(RR-L)]2(dca)3}+ leads to the formation of a 1D right-handed helical chain of Δ-2 and 1D left-handed helical chain of Λ-2, respectively, demonstrating there is a correlation between the helicity of 1D chains and the chirality of building blocks. Complex 3 forms a triangular structure of {[Ni(rac-L)(dca)]3}3+, in which the macrocyclic ligand L adopts unsymmetrical RR/RR/SS or RR/SS/SS configurations. The homochiral nature of S-1/R-1 and Δ-2/Λ-2 are confirmed by the results of solid circular dichroism (CD) spectra measurements. The magnetic properties of chiral Δ-2/Λ-2 and achiral 3 were investigated.
Co-reporter:Xiao-Dan Zheng, Mei Zhang, Long Jiang and Tong-Bu Lu
Dalton Transactions 2012 - vol. 41(Issue 6) pp:NaN1791-1791
Publication Date(Web):2011/12/12
DOI:10.1039/C1DT11825K
A novel achiral hexacarboxylic ligand L was synthesized. Spontaneous resolution occurred during the reaction of L with Eu(NO3)3 to produce a pair of enantiomers of 1a and 1b with a formula of [EuL(NO3)3(H2O)]·13H2O, which possesses 1D chiral open channels formed by triple-stranded helical chains. When heated to 60 °C, 1a releases coordinated and partial lattice H2O molecules to give a complex of [EuL(NO3)3]·4H2O (1a′), accompanied by a single-crystal-to-single-crystal transformation from 1a to 1a′, with the space group changing from P21 to P312. The dehydrated 1 can selectively adsorb water over organic solvents and exhibits reversible water adsorption upon dehydration and hydration.
Co-reporter:Mei Zhang, Yong-Liang Huang, Jia-Wei Wang and Tong-Bu Lu
Journal of Materials Chemistry A 2016 - vol. 4(Issue 5) pp:NaN1827-1827
Publication Date(Web):2016/01/14
DOI:10.1039/C5TA07813J
A main challenge for light-driven water splitting is the development of efficient and economical water oxidation catalysts (WOCs). Herein, we developed a facile approach for the preparation of a porous cobalt oxide–carbon hybrid, which was prepared by carbonizing in an inert atmosphere and subsequently air-calcining nanocrystals of zeolite imidazole framework-67 (ZIF-67), and utilized as an efficient WOC. Using Ru(bpy)3(PF6)3 as an oxidant, we got a record catalytic turnover number (TON) and a turnover frequency (TOF) of 910 ± 21 and 14.6 ± 0.4 s−1 per cobalt atom, respectively. In addition, the synthesized catalyst can also act as an efficient electrochemical WOC, with a low OER overpotential of 0.36 V at 10.0 mA cm−2 in a pH 13 medium. The superior catalyst performance can be attributed to the homogeneous dispersion of CoOx and in situ formed porous carbon, and the presence of nitrogen in the catalyst may also be attributed to its high catalytic activity.
Co-reporter:Gao-Yi Xie, Long Jiang and Tong-Bu Lu
Dalton Transactions 2013 - vol. 42(Issue 39) pp:NaN14099-14099
Publication Date(Web):2013/08/02
DOI:10.1039/C3DT51501J
Cryptand L (L = N[(CH2)2NHCH2(2,6-C10H6)CH2NH(CH2)2]3N) and its dinuclear metal cryptates [Zn2L](NO3)4 (1) and [Cu2L](ClO4)4 (2) have been prepared, and the binding properties of the cryptates with fumarate and its cis isomer maleate were investigated using fluorescent spectra, 1H NMR titrations and single crystal X-ray diffraction analysis for [(Cu2L)(fum)][ClO4]2 (3) (fum = fumarate). Thanks to the size and shape matching effect, the cryptates can selectively recognize fumarate at physiological pH, with an association constant almost 18-fold larger than that of maleate, forming a cradle-like cascade complex.
Co-reporter:Yun-Nan Gong, Long Jiang and Tong-Bu Lu
Chemical Communications 2013 - vol. 49(Issue 94) pp:NaN11115-11115
Publication Date(Web):2013/10/22
DOI:10.1039/C3CC46530F
A dynamic fluorescent metal–organic framework has been constructed using triphenylene-2,6,10-tricarboxylate and Tb3+ as building blocks, which exhibits guest-responsive structural dynamism and selective sensing of nitroaromatic explosives.
Co-reporter:Yun-Nan Gong and Tong-Bu Lu
Chemical Communications 2013 - vol. 49(Issue 70) pp:NaN7713-7713
Publication Date(Web):2013/07/22
DOI:10.1039/C3CC42268B
A stable porous metal–organic framework (MOF) containing methyl viologen cations exhibits reversible photochromic, thermochromic and fluorescence changes via host–guest interactions, and can be used for fast and selective detection of oxygen by naked eye recognition of color change within five seconds.
Co-reporter:Yong-Liang Huang, Yun-Nan Gong, Long Jiang and Tong-Bu Lu
Chemical Communications 2013 - vol. 49(Issue 17) pp:NaN1755-1755
Publication Date(Web):2013/01/23
DOI:10.1039/C3CC38730E
A porous Mg-based 3D metal–organic framework with unique nanoscale cages and two-fold interpenetrating pcu nets has been synthesized and characterized. It shows gas-uptake capacities for N2, H2, O2 and CO2 at low temperatures and selective adsorption of CO2 over O2 and N2 at room temperature.
Co-reporter:Yun-Nan Gong, Ting Ouyang, Chun-Ting He and Tong-Bu Lu
Chemical Science (2010-Present) 2016 - vol. 7(Issue 2) pp:NaN1075-1075
Publication Date(Web):2015/11/11
DOI:10.1039/C5SC02679B
A major challenge for the development of organic water oxidation catalysts is their low chemical stability and low catalytic efficiency. Herein, we first demonstrate that both the chemical stability and catalytic efficiency of an organic ligand for water oxidation can be improved by incorporating it into the framework of a stable MOF. This opens up a promising avenue for the development of stable and efficient organic water oxidation catalysts.
Co-reporter:Guang-Chuan Ou, Long Jiang, Xiao-Long Feng and Tong-Bu Lu
Dalton Transactions 2009(Issue 1) pp:NaN76-76
Publication Date(Web):2008/11/18
DOI:10.1039/B810802A
The reactions of four-coordinated transition metal macrocyclic complexes [ML](ClO4)2 (L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, M = Ni, Cu) with NH4VO3 under different conditions gave four coordination polymers of {[(CuL)0.5(H2L)1.5][H2V10O28]·6H2O}n (1·6H2O), {[NiL]3[V16O38(H2O)]·6H2O}n (2·6H2O), {[NiL][VO3]2·0.33H2O}n (3·0.33H2O), and {[CuL][VO3]2·0.33H2O}n (4·0.33H2O). Single crystal X-ray diffraction analyses reveal that four diverse vanadium polyoxoanions, [H2V10O28]4−cluster, [V16O38(H2O)]6− cage, [V6O18]6− ring, and [VO3]nn− chain, were obtained from the same reactant NH4VO3 under different conditions. In 1, the cluster anion [H2V10O28]4− alternately bridges [CuL]2+/[H2L]2+ to form a one-dimensional chain, and the [V16O38(H2O)]6− cage in 2 links three [NiL]2+ into a two-dimensional sheet. Compounds 3 and 4 show three-dimensional structures, which are constructed by the connections of hexanuclear [V6O18]6− rings with [NiL]2+ in 3, and [VO3]nn− chains with [CuL]2+ in 4, respectively, generating one-dimensional channels occupied by guest water molecules.
Co-reporter:Di-Chang Zhong, Wei-Xiong Zhang, Feng-Lei Cao, Long Jiang and Tong-Bu Lu
Chemical Communications 2011 - vol. 47(Issue 4) pp:NaN1206-1206
Publication Date(Web):2010/11/25
DOI:10.1039/C0CC03506H
A three-dimensional microporous metal–organic framework [Cd2(Tzc)2]n, which is dehydrated from [Cd2(Tzc)2(H2O)2]n, exhibits selective gas adsorption and large hydrogen sorption hysteresis.
Co-reporter:Ping Ju, Long Jiang and Tong-Bu Lu
Chemical Communications 2013 - vol. 49(Issue 18) pp:NaN1822-1822
Publication Date(Web):2013/01/28
DOI:10.1039/C3CC38519A
An unprecedented 3D dynamic porous metal–organic framework assembled from fivefold interlocked closed nanotubes has been constructed, which exhibits highly selective adsorption of CO2 over N2 and H2, as well as stepwise and hysteretic behaviors.
Co-reporter:Di-Chang Zhong, Miao Meng, Jie Zhu, Guo-Yu Yang and Tong-Bu Lu
Chemical Communications 2010 - vol. 46(Issue 24) pp:NaN4356-4356
Publication Date(Web):2010/05/12
DOI:10.1039/C000676A
An unprecedented organic–inorganic hybrid material with 3D inorganic and 3D organic connectivity has been constructed based on Cd(II) and tetrazolate-5-carboxylate, which shows a highly connected trinodal (4,8,16-c) topological net and SHG activity.
Co-reporter:Guang-Chuan Ou, Zi-Zhou Wang, Li-Zi Yang, Cun-Yuan Zhao and Tong-Bu Lu
Dalton Transactions 2010 - vol. 39(Issue 18) pp:NaN4279-4279
Publication Date(Web):2010/03/24
DOI:10.1039/B921141A
The enantiopure agents d- and l-leucine, selectively bind RR and SS enantiomers from a racemate [Ni(α-rac-L)]2+ to give {[Ni(RR-L)(d-HLeu)](ClO4)2}n (Δ-1) and {[Ni(SS-L)(l-HLeu)](ClO4)2}n (Λ-1), respectively, and leave the corresponding uninteracted SS and RR enantiomers of [Ni(α-SS-L)](ClO4)2 (S-2) and [Ni(α-RR-L)](ClO4)2 (R-2). Occasionally, a few crystals of {[Ni(RR-L)(l-HLeu)](ClO4)2}n (Δ-3) and {[Ni(SS-L)(d-HLeu)](ClO4)2}n (Λ-3) were found to have accreted with the crystals of Λ-1/R-2, and Δ-1/S-2, respectively (the yields are less than 2%). The results of X-ray crystal structural analysis reveal that Δ-1 and Λ-1, S-2 and R-2, and Δ-3 and Λ-3 are enantiomers, in which Δ-1 and Δ-3 possess 1D right-handed helical chains, while Λ-1 and Λ-3 exhibit a motif of 1D left-handed helical chains. The results of DFT calculations reveal that the single-point energies of [Ni(RR-L)(d-HLeu)]2+/[Ni(SS-L)(l-HLeu)]2+ in Δ-1/Λ-1 are 582 kJ mol−1 lower than those of [Ni(RR-L)(l-HLeu)]2+/[Ni(SS-L)(d-HLeu)]2+ in Δ-3/Λ-3, demonstrating the favorable stereo-coordination environments of [Ni(α-RR-L)]2+ and [Ni(α-SS-L)]2+ towards d and l-HLeu, respectively.
Co-reporter:Yun-Nan Gong, Miao Meng, Di-Chang Zhong, Yong-Liang Huang, Long Jiang and Tong-Bu Lu
Chemical Communications 2012 - vol. 48(Issue 98) pp:NaN12004-12004
Publication Date(Web):2012/11/05
DOI:10.1039/C2CC35461F
A μ4-Cl bridged anionic sodalite-type porous metal–organic framework (Et2NH2)3[(Cu4Cl)3(TTCA)8]·26DEF was synthesized, in which Et2NH2+ can be exchanged by Li+ cations. The results of gas measurements indicate that Et2NH2+ and Li+ are beneficial for methane and hydrogen storage, respectively.
Co-reporter:Di-Chang Zhong and Tong-Bu Lu
Chemical Communications 2016 - vol. 52(Issue 68) pp:NaN10337-10337
Publication Date(Web):2016/06/22
DOI:10.1039/C6CC03660K
The design and syntheses of supramolecular hosts for the recognition and activation of molecules and anions are one of the most active research fields in supramolecular chemistry, in which polyaza macrocyclic ligands and their complexes have drawn particular attention due to their strong host–guest interactions. This review mainly focuses on the recent progress in the recognition of molecules and anions by polyaza macrocyclic compounds including polyaza macrocycles, polyaza macrobicycles and polyaza macrotricycles, as well as the activation of molecules by polyaza macrocyclic ligands and their metal complexes.
