Marilyn M. Olmstead

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Name: Olmstead, Marilyn M.

Organization: University of California , USA

Department: Department of Chemistry

Title: (PhD)

TOPICS

Inorganic Chemistry

Material Chemistry

Fullerene

Chemicals
References

Structural and Electrochemical Property Correlations of Metallic Nitride Endohedral Metallofullerenes

Co-reporter:Xavier Aparicio-Anglès;Brandon Q. Mercado;Alan L. Balch;Josep M. Poblet;Luis Echegoyen;Antonio Rodríguez-Fortea;Anna Clotet;Bevan Elliott;Manuel N. Chaur

The Journal of Physical Chemistry C August 5, 2010 Volume 114(Issue 30) pp:13003-13009

Publication Date(Web):2017-2-22

DOI:10.1021/jp104352d

Structural and electrochemical property correlations of metallic nitride endohedral metallofullerenes (MN EMFs) were studied in detail. The electrochemical properties of these compounds are strongly dependent on the symmetry of the carbon cage and, except for the Sc3N cluster, are independent of the nature of the metallic cluster due to the localization of the HOMO and LUMO on the carbon cage. The X-ray structure of Gd3N@C86 shows that the cage obeys the isolated pentagon rule and uses a cage with D3 symmetry, in agreement with previously published data for Tb3N@C86, the only other structurally characterized C86 MN EMF. The electrochemical properties of different MN EMFs are used to probe the structural features of these compounds. Electrochemistry was used to determine the relative abundances of the D5h and Ih isomers of M3N@C80 compounds, whereas HPLC allowed the analysis of larger MN EMFs. The binding energies (BEs) were computed for different MN EMFs, and a strong correlation between the BE (of the cluster and fullerene cage) and the corresponding abundance of the given MN EMF was obtained. The results account for the different template stages and for the relative abundances observed for MN EMFs.

X-ray Crystallographic Characterization of New Soluble Endohedral Fullerenes Utilizing the Popular C82 Bucky Cage. Isolation and Structural Characterization of Sm@C3v(7)-C82, Sm@Cs(6)-C82, and Sm@C2(5)-C82

Co-reporter:Hua Yang, Hongxiao Jin, Xinqing Wang, Ziyang Liu, Meilan Yu, Fukun Zhao, Brandon Q. Mercado, Marilyn M. Olmstead, and Alan L. Balch

Journal of the American Chemical Society August 29, 2012 Volume 134(Issue 34) pp:14127-14136

Publication Date(Web):August 3, 2012

DOI:10.1021/ja304867j

Three isomers of Sm@C82 that are soluble in organic solvents were obtained from the carbon soot produced by vaporization of hollow carbon rods doped with Sm2O3/graphite powder in an electric arc. These isomers were numbered as Sm@C82(I), Sm@C82(II), and Sm@C82(III) in order of their elution times from HPLC chromatography on a Buckyprep column with toluene as the eluent. The identities of isomers, Sm@C82(I) as Sm@Cs(6)-C82, Sm@C82(II) as Sm@C3v(7)-C82, and Sm@C82(III) as Sm@C2(5)-C82, were determined by single-crystal X-ray diffraction on cocrystals formed with Ni(octaethylporphyrin). For endohedral fullerenes like La@C82, which have three electrons transferred to the cage to produce the M3+@(C82)3– electronic distribution, generally only two soluble isomers (e.g., La@C2v(9)-C82 (major) and La@Cs(6)-C82 (minor)) are observed. In contrast, with samarium, which generates the M2+@(C82)2– electronic distribution, five soluble isomers of Sm@C82 have been detected, three in this study, the other two in two related prior studies. The structures of the four Sm@C82 isomers that are currently established are Sm@C2(5)-C82, Sm@Cs(6)-C82, Sm@C3v(7)-C82, and Sm@C2v(9)-C82. All of these isomers obey the isolated pentagon rule (IPR) and are sequentially interconvertable through Stone–Wales transformations.

Interrelationships between the tetrahedral and planar polymorphs of bis(3-ethylamino-1-phenyl-but-2-en-1-ono)nickel(II) and structural comparisons with related CoII, NiII, CuII, and ZnII complexes

Co-reporter:Xian B. Powers;Kamran B. Ghiassi;Joshua T. Greenfield;Alan L. Balch

CrystEngComm (1999-Present) 2017 vol. 19(Issue 24) pp:3244-3253

Publication Date(Web):2017/06/20

DOI:10.1039/C7CE00638A

Conditions for the crystallization and interconversion of the green and brown polymorphs of bis(3-ethylamino-1-phenyl-but-2-en-1-ono)nickel(II) (Ni(B–Et)2), which contain planar and tetrahedral complexes in accord with previous magnetic and spectroscopic studies, have been determined. Additionally, the series of β-diketoamine-containing complexes, M(B–Et)2 and M(B–Bn)2, (M = CoII, NiII, CuII, ZnII) obtained from condensation of benzoylacetone (B) with either ethylamine (Et) or benzylamine (Bn) followed by treatment with [MCl4]2− under basic conditions has been prepared and their structures characterized crystallographically. In contrast to Ni(B–Et)2, Ni(B–Bn)2 has been crystallized only in the planar form. M(B–Et)2 and M(B–Bn)2 (M = Co or Zn) have similar, nearly tetrahedral structures, while Cu(B–Et)2 and Cu(B–Bn)2 have structures that are decidedly intermediate between tetrahedral and planar. Despite the abilities of these complexes to exist in tetrahedral, planar, or intermediate structures in solution, it has not been possible to induce much structural variation in crystalline forms. While two polymorphs of Zn(B–Bn)2 have been obtained, both have similar, tetrahedral structures. Only Ni(B–Et)2 crystallizes in both planar and tetrahedral forms. None of the complexes formed cocrystals with fullerenes or solvates in which structural variation as seen in Ni(B–Et)2 occurred.

An ordering phase transition, short hydrogen bonds and high Z′ in the structure of Ni(Hpydc)2·3H2O

Co-reporter:Zohreh Derikv;Xian B. Powers

Acta Crystallographica Section B 2017 Volume 73(Issue 3) pp:413-418

Publication Date(Web):2017/06/01

DOI:10.1107/S2052520617004334

The structure of Ni(Hpydc)2·3H2O (H2pydc = pyridine-2,6-dicarboxylic acid, also known as dipicolinic acid) has been reinvestigated at variable temperatures. At room temperature, it matches the known structure in the space group P21/c, but at 180 K it undergoes a phase transformation to a twinned structure in Cc. By 120 K, the structure is ordered and twinned with Z′ = 4, and shows interesting short hydrogen-bonding interactions that include the formation of hydroxonium species.

Zigzag Sc2C2 Carbide Cluster inside a [88]Fullerene Cage with One Heptagon, Sc2C2@Cs(hept)-C88: A Kinetically Trapped Fullerene Formed by C2 Insertion?

Co-reporter:Chia-Hsiang Chen, Laura Abella, Maira R. Cerón, Miguel A. Guerrero-Ayala, Antonio Rodríguez-Fortea, Marilyn M. Olmstead, Xian B. Powers, Alan L. Balch, Josep M. Poblet, and Luis Echegoyen

Journal of the American Chemical Society 2016 Volume 138(Issue 39) pp:13030-13037

Publication Date(Web):September 5, 2016

DOI:10.1021/jacs.6b07912

Tethered bis-pyrrolidine additions to C70: Some unexpected and new regioisomers

Co-reporter:Maira R. Cerón, Marta Izquierdo, Amineh Aghabali, Sophie P. Vogel, Marilyn M. Olmstead, Alan L. Balch, Luis Echegoyen

Carbon 2016 Volume 105() pp:394-400

Publication Date(Web):August 2016

DOI:10.1016/j.carbon.2016.04.044

Four easily isolable bis-pyrrolidine-C70 regioisomers were synthesized and characterized by spectroscopic techniques. The four [70]fullerene bis-adducts were unambiguously assigned using spectroscopic techniques and X-ray crystallography, as the β-2-β, α-2-α, α-1-β and α-1-α regioisomers.

Isolation and Crystallographic Characterization of Gd3N@D2(35)-C88 through Non-Chromatographic Methods

Co-reporter:Steven Stevenson, Kristine D. Arvola, Muska Fahim, Benjamin R. Martin, Kamran B. Ghiassi, Marilyn M. Olmstead, and Alan L. Balch

Inorganic Chemistry 2016 Volume 55(Issue 1) pp:62-67

Publication Date(Web):September 30, 2015

DOI:10.1021/acs.inorgchem.5b01814

While several nonchromatographic methods are available for the isolation and purification of endohedral fullerenes of the type M3N@Ih-C80, little work has been done that would allow other members of the M3N@C2n family to be isolated with minimal chromatography. Here, we report that Gd3N@D2(35)-C88 can be isolated from the multitude of endohedral and empty cage fullerenes present in carbon soot obtained by electric-arc synthesis using Gd2O3-doped graphite rods. The procedure developed utilizes successive precipitation with the Lewis acids CaCl2 and ZnCl2 followed by treatment with amino-functionalized silica gel. The structure of the product was identified by single-crystal X-ray diffraction.

Regioselective Synthesis and Crystallographic Characterization of Isoxazoline-Ring-Fused Derivatives of Sc3N@Ih-C80 and C60

Co-reporter:Lipiao Bao, Muqing Chen, Wangqiang Shen, Changwang Pan, Kamran B. Ghiassi, Marilyn M. Olmstead, Alan L. Balch, Takeshi Akasaka, and Xing Lu

Inorganic Chemistry 2016 Volume 55(Issue 9) pp:4075

Publication Date(Web):April 21, 2016

DOI:10.1021/acs.inorgchem.6b00631

Highly regioselective 1,3-dipolar cycloaddition of 3,5-dichloro-2,4,6-trimethoxybenzonitrile oxide (1) to Sc3N@Ih-C80 or C60 affords the corresponding isoxazoline-ring-fused derivatives Sc3N@Ih-C80(C10H9O4NCl2) (2a) and C60(C10H9O4NCl2) (2b). 2a represents the first example of an endohedral metallofullerene derivative with an isoxazoline ring. Crystallographic and NMR spectroscopic studies reveal a [5,6]-bond addition pattern in 2a but a [6,6]-bond addition manner in 2b.

Crystal Engineering Gone Awry. What a Difference a Few Methyl Groups Make in Fullerene/Porphyrin Cocrystallization

Co-reporter:Kamran B. Ghiassi, Xian B. Powers, Joseph Wescott, Alan L. Balch, and Marilyn M. Olmstead

Crystal Growth & Design 2016 Volume 16(Issue 1) pp:447-455

Publication Date(Web):December 7, 2015

DOI:10.1021/acs.cgd.5b01449

Two related nickel(II) porphyrins, etioporphyrin-I (Etio-I) and octaethylporphyrin (OEP), were cocrystallized with C70 to produce the new cocrystal structures C70·Ni(Etio-I)·2C6H6 and C70·Ni(OEP)·2C6H6. Etio-I is a variant of OEP, where four alternating ethyl groups from OEP are replaced with methyl substituents. This isomer of etioporphyrin has the potential to act as an agent in chiral sorting of asymmetric fullerenes. However, the replacement of four ethyl groups has nontrivial structural consequences. Further host–guest investigation of M(Etio-I) (M = Co, Ni, Cu, Zn) with C60 or C70 was conducted, producing new X-ray structures of Co(Etio-I) and Zn(Etio-I), and a redetermination of Ni(Etio-I). Despite numerous and varied attempts, C60 cocrystallized with M(Etio-I) could not be obtained.

Silver(I)-Mediated Modification, Dimerization, and Polymerization of an Open-Cage Fullerene

Co-reporter:Amineh Aghabali, Sharon Jun, Marilyn M. Olmstead, and Alan L. Balch

Journal of the American Chemical Society 2016 Volume 138(Issue 50) pp:

Publication Date(Web):November 21, 2016

DOI:10.1021/jacs.6b10394

The reactions of the open-cage fullerene, MMK-9, with an open 12-membered ring on its surface and silver(I) salts have been examined. The structure of MMK-9 itself has been determined by single-crystal X-ray diffraction. MMK-9 reacts with silver trifluoroacetate in air to form the dimer, {MMK-9(OCH3)5Ag(AgO2CCF3)}2. Remarkably, five MeO groups have added to the surface of the open cage in a pattern that surrounds a pentagon immediately adjacent to the opening in the cage. Dioxygen has been implicated as the oxidant in this unusual addition of five groups to the open cage. Two silver ions connected to each other by a short argentophillic interaction reside at the core of the centrosymmetric dimer. The reaction of silver nitrate with MMK-9 yields the crystalline polymer, [{MMK-9(OCH3)5Ag(AgOCH3)}2·H2O]n. This polymer consists of dimeric {MMK-9(OCH3)5Ag}2 units that are connected into strands through silver ions, which are chelated by the amine functions of one open cage and bound in η2-fashion to a pair of carbon atoms on an adjacent open cage.

Tethered Bisadducts of C60 and C70 with Addends on a Common Hexagonal Face and a 12-Membered Hole in the Fullerene Cage

Co-reporter:Maira R. Cerón; Marta Izquierdo; Amineh Aghabali; Juan A. Valdez; Kamran B. Ghiassi; Marilyn M. Olmstead; Alan L. Balch; Fred Wudl;Luis Echegoyen

Journal of the American Chemical Society 2015 Volume 137(Issue 23) pp:7502-7508

Publication Date(Web):May 18, 2015

DOI:10.1021/jacs.5b03768

The regioselective synthesis of easily isolable pure bismethano derivatives of C60 and C70 with high steric congestion is described using 1,3-dibenzoylpropane bis-p-toluenesulfonyl hydrazone as the addend precursor. When the addition occurs at two [6,6] ring junctions within the same hexagon, bisadducts with mirror symmetry are obtained for both C60 and C70. When the addition occurs at two [5,6] ring junctions in C60, a symmetrical adduct is formed, which readily undergoes photo-oxygenation and ring opening to yield a fullerene with a hole in the cage. In this work, we also propose a simple and general system to name all of the possible [6,6] bisadduct isomers on C70.

Beyond the Butterfly: Sc2C2@C2v(9)-C86, an Endohedral Fullerene Containing a Planar, Twisted Sc2C2 Unit with Remarkable Crystalline Order in an Unprecedented Carbon Cage

Co-reporter:Chia-Hsiang Chen; Kamran B. Ghiassi; Maira R. Cerón; Miguel A. Guerrero-Ayala; Luis Echegoyen; Marilyn M. Olmstead;Alan L. Balch

Journal of the American Chemical Society 2015 Volume 137(Issue 32) pp:10116-10119

Publication Date(Web):August 3, 2015

DOI:10.1021/jacs.5b06425

The synthesis, isolation, and characterization of a new endohedral fullerene, Sc2C88, is reported. Characterization by single crystal X-ray diffraction revealed that it is the carbide Sc2C2@C2v(9)-C86 with a planar, twisted Sc2C2 unit inside a previously unseen C2v(9)-C86 fullerene cage.

Formation of a Stable Complex, RuCl2(S2CPPh3)(PPh3)2, Containing an Unstable Zwitterion from the Reaction of RuCl2(PPh3)3 with Carbon Disulfide

Co-reporter:Kamran B. Ghiassi, Daniel T. Walters, Michael M. Aristov, Natalia D. Loewen, Louise A. Berben, Melissa Rivera, Marilyn M. Olmstead, and Alan L. Balch

Inorganic Chemistry 2015 Volume 54(Issue 9) pp:4565-4573

Publication Date(Web):April 10, 2015

DOI:10.1021/acs.inorgchem.5b00461

New insight into the complexity of the reaction of the prominent catalyst RuCl2(PPh3)3 with carbon disulfide has been obtained from a combination of X-ray diffraction and 31P NMR studies. The red-violet compound originally formulated as a cationic π-CS2 complex, [RuCl(π-CS2)(PPh3)3]Cl, has been identified as a neutral molecule, RuCl2(S2CPPh3)(PPh3)2, which contains the unstable zwitterion S2CPPh3. In the absence of RuCl2(PPh3)3, there is no sign of a reaction between triphenylphosphine and carbon disulfide, although more basic trialkylphosphines form red adducts, S2CPR3. Despite the presence of an unstable ligand, RuCl2(S2CPPh3)(PPh3)2 is remarkably stable. It survives melting at 173–174 °C intact, is stable to air, and undergoes reversible electrochemical oxidation to form a monocation. When the reaction of RuCl2(PPh3)3 with carbon disulfide is conducted in the presence of methanol, crystals of orange [RuCl(S2CPPh3)(CS)(PPh3)2]Cl·2MeOH and yellow RuCl2(CS)(MeOH)(PPh3)2 also form. 31P NMR studies indicate that the unsymmetrical dinuclear complex (SC)(Ph3P)2Ru(μ-Cl)3Ru(PPh3)2Cl is the initial product of the reaction of RuCl2(PPh3)3 with carbon disulfide. A path connecting the isolated products is presented.

New Insights into the Structural Complexity of C60·2S8: Two Crystal Morphologies, Two Phase Changes, Four Polymorphs

Co-reporter:Kamran B. Ghiassi, Susanne Y. Chen, Joseph Wescott, Alan L. Balch, and Marilyn M. Olmstead

Crystal Growth & Design 2015 Volume 15(Issue 1) pp:404-410

Publication Date(Web):November 11, 2014

DOI:10.1021/cg501486x

Three new polymorphs of C60·2S8 were discovered. The previously known structure (first reported by Roth and Adelmann in 1993 hereby designated as α) crystallizes in space group C2/c with Z = 4 and changes to a triclinic structure (β) in space group P1̅ with Z = 4 when the temperature is decreased below 260 K. The room-temperature structure was reinvestigated, and the new, ordered, low-temperature structure is described. A new, concomitant, polymorph (γ) crystallizes in space group P21/c with Z = 4 at room temperature and undergoes a phase change to Pc (δ) with Z = 4 when the temperature is decreased below 180 K. As indicated by geometric and temperature factor changes, it is clear that the low-temperature phases represent an increase in the level of order in the arrangement of C60 molecules. Both of the phase changes are reversible.

Waves of Halogen–Halogen Bond Formation in the Cocrystallization of Hexabromobenzene and 1,2,4,5-Tetrabromobenzene with C70

Co-reporter:Kamran B. Ghiassi, Joseph Wescott, Susanne Y. Chen, Alan L. Balch, and Marilyn M. Olmstead

Crystal Growth & Design 2015 Volume 15(Issue 5) pp:2480-2485

Publication Date(Web):March 25, 2015

DOI:10.1021/acs.cgd.5b00256

The single crystal X-ray structures of three well-ordered cocrystals of C70 with brominated benzenes are examined. The crystals are those of C70·C6Br6·C7H8, C70·C6Br6·C6H6, and C70·2(1,2,4,5-tetrabromobenzene)·CS2. While all three structures exhibit extensive van der Waals interactions, the presence of a wavelike C–Br---Br structural motif is a distinctive part of the cocrystal assembly. In these three crystal structures, it is observed that the Br---Br interactions are a cross between type I and II halogen–halogen bonds. In our hands, this structural motif does not occur in structures with C60.

2-Aminoethanol Extraction as a Method for Purifying Sc3N@C80 and for Differentiating Classes of Endohedral Fullerenes on the Basis of Reactivity

Co-reporter:Evan A. Sarina;Dr. Bron Q. Mercado;Dr. Jimmy U. Franco;Dr. Christopher J. Thompson;Dr. Michael L. Easterling;Dr. Marilyn M. Olmstead;Dr. Alan L. Balch

Chemistry - A European Journal 2015 Volume 21( Issue 47) pp:17035-17043

Publication Date(Web):

DOI:10.1002/chem.201502415

Abstract

Extraction with 2-aminoethanol is an inexpensive method for removing empty cage fullerenes from the soluble extract from electric-arc-generated fullerene soot that contains endohedral metallofullerenes of the type Sc₃N@C_2n (n=34, 39, 40). Our method of separation exploits the fact that C₆₀, C₇₀, and other larger, empty cage fullerenes are more susceptible to nucleophilic attack than endohedral fullerenes and that these adducts can be readily extracted into 2-aminoethanol. This methodology has also been employed to examine the reactivity of the mixture of soluble endohedral fullerenes that result from doping graphite rods used in the Krätschmer–Huffman electric-arc generator with the oxides of Y, Lu, Dy, Tb, and Gd. For example, with Y₂O₃, we were able to detect by mass spectrometry several new families of endohedral fullerenes, namely Y₃C₁₀₈ to Y₃C₁₂₆, Y₃C₁₀₇ to Y₃C₁₂₅, Y₄C₁₂₈ to Y₄C₁₄₆, that resisted reactivity with 2-aminoethanol more than the empty cage fullerenes and the mono- and dimetallo fullerenes. The discovery of the family Y₃C₁₀₇ to Y₃C₁₂₅ with odd numbers of carbon atoms is remarkable, since fullerene cages must involve even numbers of carbon atoms. The newly discovered families of endohedral fullerenes with the composition M₄C_2n (M=Y, Lu, Dy, Tb, and Gd) are unusually resistant to reaction with 2-aminoethanol. Additionally, the individual endohedrals, Y₃C₁₁₂ and M₃C₁₀₂ (M=Lu, Dy, Tb and Gd), were remarkably less reactive toward 2-aminoethanol.

Synthesis and Structure of LaSc2N@Cs(hept)-C80 with One Heptagon and Thirteen Pentagons

Co-reporter:Dr. Yang Zhang;Kamran B. Ghiassi;Qingming Deng;Nataliya A. Samoylova; Marilyn M. Olmstead; Alan L. Balch;Dr. Alexey A. Popov

Angewandte Chemie 2015 Volume 127( Issue 2) pp:505-509

Publication Date(Web):

DOI:10.1002/ange.201409094

Abstract

The synthesis and single-crystal X-ray structural characterization of the first endohedral metallofullerene to contain a heptagon in the carbon cage are reported. The carbon framework surrounding the planar LaSc₂N unit in LaSc₂N@C_s(hept)-C₈₀ consists of one heptagon, 13 pentagons, and 28 hexagons. This cage is related to the most abundant I_h-C₈₀ isomer by one Stone–Wales-like, heptagon/pentagon to hexagon/hexagon realignment. DFT computations predict that LaSc₂N@C_s(hept)-C₈₀ is more stable than LaSc₂N@D_5h-C₈₀, and suggests that the low yield of the heptagon-containing endohedral fullerene may be caused by kinetic factors.

A zwitterion produced by a strong intramolecular NB interaction in 1-hydroxy-2-(pyridin-2-ylcarbonyl)benzo[d][1,2,3]diazaborinine

Co-reporter:Evan A. Sarina, ;Divya Kanichar ;Michael P. Groziak

Acta Crystallographica Section C 2015 Volume 71( Issue 12) pp:1085-1088

Publication Date(Web):

DOI:10.1107/S2053229615021841

2-Acylated 2,3,1-benzodiazaborines can display unusual structures and reactivities. The crystal structure analysis of the boron heterocycle obtained by condensing 2-formylphenylboronic acid and picolinohydrazide reveals it to be an NB-chelated zwitterionic tetracycle (systematic name: 1-hydroxy-11-oxo-9,10,17λ⁵-triaza-1λ⁴-boratetracyclo[8.7.0.0^2,7.0^12,17]heptadeca-3,5,7,12,14,16-hexaen-17-ylium-1-uide), C₁₃H₁₀BN₃O₂, produced by the intramolecular addition of the Lewis basic picolinoyl N atom of 1-hydroxy-2-(pyridin-2-ylcarbonyl)benzo[d][1,2,3]diazaborinine to the boron heterocycle B atom acting as a Lewis acid. Neither of the other two pyridinylcarbonyl isomers (viz. nicotinoyl and isonicotinoyl) are able to adopt such a structure for geometric reasons. A favored yet reversible chelation equilibrium provides an explanation for the slow D₂O exchange observed for the OH resonance in the ¹H NMR spectrum, as well as for its unusual upfield chemical shift. Deuterium exchange may take place solely in the minor open (unchelated) species present in solution.

Synthesis and Structure of LaSc2N@Cs(hept)-C80 with One Heptagon and Thirteen Pentagons

Co-reporter:Dr. Yang Zhang;Kamran B. Ghiassi;Qingming Deng;Nataliya A. Samoylova; Marilyn M. Olmstead; Alan L. Balch;Dr. Alexey A. Popov

Angewandte Chemie International Edition 2015 Volume 54( Issue 2) pp:495-499

Publication Date(Web):

DOI:10.1002/anie.201409094

Abstract

Preparation and Crystallographic Characterization of C60{η1-Ru(CO)2(η5-C5H5)}2: A Locally Crowded Organometallic Fullerene Without the Usual η2-Bonding

Co-reporter:Faye L. Bowles ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society 2014 Volume 136(Issue 9) pp:3338-3341

Publication Date(Web):February 17, 2014

DOI:10.1021/ja4120677

The reaction of {(η5-C5H5)Ru(CO)2}2 with C60 in toluene solution under thermal or photolytic conditions produces C60{η1-Ru(CO)2(η5-C5H5)}2, whose structure has been determined by single crystal X-ray diffraction. The two Ru(CO)2(η5-C5H5) units are bound at the opposite ends of a hexagon on the fullerene surface and are closely intertwined.

Regioselective Benzyl Radical Addition to an Open-Shell Cluster Metallofullerene. Crystallographic Studies of Cocrystallized Sc3C2@Ih-C80 and Its Singly Bonded Derivative

Co-reporter:Hongyun Fang, Hailin Cong, Mitsuaki Suzuki, Lipiao Bao, Bing Yu, Yunpeng Xie, Naomi Mizorogi, Marilyn M. Olmstead, Alan L. Balch, Shigeru Nagase, Takeshi Akasaka, and Xing Lu

Journal of the American Chemical Society 2014 Volume 136(Issue 29) pp:10534-10540

Publication Date(Web):July 7, 2014

DOI:10.1021/ja505858y

The endohedral fullerene once erroneously identified as Sc3@C82 was recently shown to be Sc3C2@Ih-C80, the first example of an open-shell cluster metallofullerene. We herein report that benzyl bromide (1) reacts with Sc3C2@ Ih-C80 via a regioselective radical addition that affords only one isomer of the adduct Sc3C2@Ih-C80(CH2C6H5) (2) in high yield. An X-ray crystallographic study of 2 demonstrated that the benzyl moiety is singly bonded to the fullerene cage, which eliminates the paramagnetism of the endohedral in agreement with the ESR results. Interestingly, X-ray results further reveal that the 3-fold disordered Sc3C2 cluster adopts two different configurations inside the cage. These configurations represent the so-called “planar” form and the computationally predicted, but not crystallographically characterized, “trifoliate” form. It is noteworthy that this is the first crystallographic observation of the “trifoliate” form for the Sc3C2 cluster. In contrast, crystallographic investigation of a Sc3C2@Ih-C80/Ni(OEP) cocrystal, in which the endohedral persists in an open-shell structure with paramagnetism, indicates that only the former form occurs in pristine Sc3C2@ Ih-C80. These results demonstrate that the cluster configuration in EMFs is highly sensitive to the electronic structure, which is tunable by exohedral modification. In addition, the electrochemical behavior of Sc3C2@Ih-C80 has been markedly changed by the radical addition, but the absorption spectra of the pristine and the derivative are both featureless. These results suggest that the unpaired electron of Sc3C2@Ih-C80 is buried in the Sc3C2 cluster and does not affect the electronic configuration of the cage.

Zipping up fullerenes into polymers using rhodium(II) acetate dimer and N(CH2CH2)2NC60 as building blocks

Co-reporter:Amineh Aghabali, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2014 vol. 50(Issue 96) pp:15152-15155

Publication Date(Web):16 Oct 2014

DOI:10.1039/C4CC06995A

The reaction of Rh2(O2CCH3)4 with the functionalized fullerene N(CH2CH2)2NC60 can produce a linear, crystalline polymer or can trap free C60 or C70 molecules between similar chains.

Cocrystallization of C60 or C70 with the Bowl-Shaped Hydrocarbon Hexakis[(E)-3,3-dimethyl-1-butenyl]benzene To Form Chains of Clamshell Assemblies

Co-reporter:Kamran B. Ghiassi, Susanne Y. Chen, Peter Prinz, Armin de Meijere, Marilyn M. Olmstead, and Alan L. Balch

Crystal Growth & Design 2014 Volume 14(Issue 8) pp:4005-4010

Publication Date(Web):July 7, 2014

DOI:10.1021/cg500603c

The bowl-shaped hydrocarbon hexakis[(E)-3,3-dimethyl-1-butenyl]benzene (HB) has been cocrystallized with either C60 or C70 to form clamshell-like assemblies with the fullerenes residing within the concave surfaces of two HB molecules. The structures of these two crystals have been determined by single-crystal X-ray diffraction. The HB molecules exhibit back-to-back stacking and close contacts in both cocrystals. This trait is remarkably similar to the packing seen in cases in which fullerenes cocrystallize with MII(OEP), where OEP is the dianion of octaethylporphyrin and M is generally Ni or Co. The C60 structure features an ordered cage with a disordered solvent position, while the C70 structure exhibits two orientations of the cage, all other components being ordered.

Incorporation of the Similarly Sized Molecules, Diiodine and Carbon Disulfide, into Cocrystals Formed with the Fullerenes, C60 or C70

Co-reporter:Kamran B. Ghiassi, Faye L. Bowles, Susanne Y. Chen, Marilyn M. Olmstead, and Alan L. Balch

Crystal Growth & Design 2014 Volume 14(Issue 10) pp:5131-5136

Publication Date(Web):August 20, 2014

DOI:10.1021/cg500817w

Cocrystallization of diiodine and carbon disulfide with the two common fullerenes, C60 and C70, has been examined. The binary cocrystal, C70·I2, readily formed when a solution of diiodine in diethyl ether was layered over C70 dissolved in toluene, chlorobenzene, or 1,2-dichlorobenzene, but no binary cocrystal of diiodine and C60 could be obtained despite persistent efforts. The ternary cocrystal, C70·0.85I2·0.15CS2, which was grown from a carbon disulfide solution of C70 and a benzene solution of diiodine, is isostructural with C70·I2 but has 15% of the diiodine sites replaced with carbon disulfide. In contrast, C70·0.68I2·0.32CS2, which was obtained from diffusion of a cyclohexane solution of diiodine into a carbon disulfide solution of C70, is a unique ternary cocrystal that is not related to any binary cocrystal of C70 with diiodine or carbon disulfide. Crystals of 2C60·2.46CS2·0.54I2 were obtained from a saturated carbon disulfide solution of diiodine and C60. Black crystals of 2C60·2.46CS2·0.54I2 form in a different space group from those of the solvate 2C60·3CS2 but have a very similar structure. Remarkably, diiodine molecules fractionally replace carbon disulfide in only two of the three independent sites within this crystal.

Bioorganometallic Chemistry. 27. Synthetic, X-ray Crystallographic, and Competitive Binding Studies in the Reactions of Nucleobases, Nucleosides, and Nucleotides with [Cp*Rh(H2O)3](OTf)2, as a Function of pH, and the Utilization of Several Cp*Rh–DNA Base Complexes in Host–Guest Chemistry

Co-reporter:David P. Smith, Hong Chen, Seiji Ogo, Ana I. Elduque, Miriam Eisenstein, Marilyn M. Olmstead, and Richard H. Fish

Organometallics 2014 Volume 33(Issue 10) pp:2389-2404

Publication Date(Web):April 22, 2014

DOI:10.1021/om500106r

The reactions of the air- and water-stable tris(aqua) complex [Cp*Rh(H2O)3](OTf)2 (1; OTf = trifluoromethanesulfonate) with nucleobases and nucleosides that included 9-methyladenine (9-MA), 9-ethylguanine (9-EG), 9-methylhypoxanthine (9-MH), 9-ethylhypoxanthine (9-EH), 1-methylcytosine (1-MC), 1-methylthymine (1-MT), adenosine (Ado), and guanosine (Guo) provided new bonding modes, all as a function of pH. The 9-MA nucleobase provided a novel cyclic trimer, at pH 6, characteristic for all Ado complexes: [Cp*Rh(μ2-η1(N1):η2(N6,N7)-9-MA/Ado)]3(OTf)3. The Cp*Rh(9-EG) and Cp*Rh(Guo) complexes showed N7 and 6-C═O binding modes in water, [Cp*Rh((η2(N7,O6)-9-EG/Guo)(OH)](OTf), and no cyclic trimer products, due to a pronounced steric effect of the 2-amino group. This was shown convincingly by the results with 9-MH and 9-EH, which did form cyclic trimers at pH 6.1, [Cp*Rh(μ2-η1(N1):η2(N7,O6)-9-MH/9-EH)]3(OTf)3, with a structure similar to that of 9-EG, but with no 2-amino group available. At pH 10.2, the pKa of the 9-MH’s NH1 hydrogen dictated the structure, providing a μ-hydroxy dimer, trans-[Cp*Rh(η1(N1)-9-MH)(μ-OH)]2(OTf)2, while in methanol the same reaction provided a mononuclear complex, [Cp*Rh(η1(N7)-9-MH)(MeOH)2](OTf)2. The reaction of 1 and 1-MC, at pH 5.4, provided another μ-hydroxy dimer with intramolecular H bonding of the O and H atoms of the μ-OH groups (H-acceptor and H-donor, respectively), trans-[Cp*Rh(η1(N3)-1-MC)(μ-OH)]2(OTf)2, while in acetone, the product was a monomeric complex, [(η5-Cp*Rh)(η1(N3)-1-MC)(η2(O2,N3)-1-MC)](OTf)2. The reaction of 1 and 1-MT at pH 10 showed the initial complex 1 being converted to its equilibrium complex, [(Cp*Rh)2(μ-OH)3]+, and this led to two components being formed. The anionic component was a linear [(η1(N3)-MT)–RhI–(η1(N3)-MT)]– (12e RhI center) assembly, formed via a presumed reductive elimination of Cp*OH, and included an orthogonal array of two thymine planes. The cationic component was [(Cp*Rh)2(μ-OH)3]+, with its Cp* moiety being π–π stacked with thymine rings, as well as the π–π interactions of two thymine rings: {[RhI(η1(N3)-1-MT)2]2[(Cp*Rh)2(μ-OH)3]3}OH. The competitive order of nucleoside reactivity was Ado ≫ Guo, while for the nucleotides it was GMP > AMP ≫ CMP ≈ TMP. Finally, we also discuss several examples of the utilization of these unique Cp*Rh–DNA base complexes, as aqueous hosts for molecular recognition of aromatic amino acids and as NMR shift reagents for many organic compounds.

Orientational variation, solvate composition and molecular flexibility in well-ordered cocrystals of the fullerene C70 with bis(ethylenedithio)tetrathiafulvalene

Co-reporter:Kamran B. Ghiassi, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2013 vol. 49(Issue 91) pp:10721-10723

Publication Date(Web):04 Oct 2013

DOI:10.1039/C3CC46367B

Cocrystallization of C70 with bis(ethylenedithio)tetrathiafulvalene (ET) produces two different solvates, C70·ET·C6H6 and 2C70·2ET·CS2, which show distinctly different overlap between the fullerene and ET molecules.

Isolation and Crystallographic Characterization of Sm@C2v(3)-C80 Through Cocrystal Formation with NiII(octaethylporphyrin) or Bis(ethylenedithio)tetrathiafulvalene

Co-reporter:Hua Yang, Zhimin Wang, Hongxiao Jin, Bo Hong, Ziyang Liu, Christine M. Beavers, Marilyn M. Olmstead, and Alan L. Balch

Inorganic Chemistry 2013 Volume 52(Issue 3) pp:1275-1284

Publication Date(Web):January 23, 2013

DOI:10.1021/ic301794r

Sm@C2v(3)-C80 has been separated from the carbon soot produced by electrical arc vaporization of graphite rods doped with Sm2O3 and purified. Its structure has been determined by single crystal X-ray diffraction using cocrystals obtained from either NiII(octaethylporphyrin) (NiII(OEP)) to form Sm@C2v(3)-C80·NiII(OEP)·1.68(toluene)·0.32(benzene) or bis(ethylenedithio)-tetrathiafulvalene (ET) to produce Sm@C2v(3)-C80·ET·0.5(toluene). Thus, this study offers the first opportunity to compare a common endohedral fullerene in two different cocrystals. Both cocrystals provide consistent information on the basic structure of Sm@C2v(3)-C80 but show that the distribution of samarium ion sites inside the carbon cage depends upon whether NiII(OEP) or ET is present. The samarium ion is disordered in both structures, but the prominent sites lie slightly off the 2-fold symmetry axis of the cage. Computational studies at the B3LYP level indicate that Sm@C2v(3)-C80 is more stable than any of the other six isomers of Sm@C80 that obey the isolated pentagon rule (IPR). The surface electrostatic potential of the interacting components in the cocrystals has been examined to identify factors responsible for the ordering of the fullerene cages. The regions of the NiII(OEP) or ET molecules that are closest to the fullerene display negative potential, while the corresponding regions of the endohedral fullerene show positive potential in a consistent fashion in both cocrystals.

Ordered Structures from Crystalline Carbon Disulfide Solvates of the Nano-Tubular Fullerenes D5h(1)-C90 and D5h-C70

Co-reporter:Faye L. Bowles, Brandon Q. Mercado, Kamran B. Ghiassi, Susanne Y. Chen, Marilyn M. Olmstead, Hua Yang, Ziyang Liu, and Alan L. Balch

Crystal Growth & Design 2013 Volume 13(Issue 10) pp:4591-4598

Publication Date(Web):August 26, 2013

DOI:10.1021/cg401138g

The structures of three crystalline solvates, D5h(1)-C90·CS2, D5h-C70·3CS2, and 2(D5h-C70)·3CS2, of nanotubular fullerenes have been determined by single crystal X-ray diffraction. Despite the marked tendency for fullerenes to disorder, the carbon cages in all three structures are fully ordered at 100(2) K for D5h(1)-C90·CS2 and 90 K for the other two crystals. Moreover, the carbon disulfide molecules are also ordered, except for the case of D5h(1)-C90·CS2, where there is a minor disorder in the solvate location. The molecular packing in D5h(1)-C90·CS2 reflects the nanotubular nature of the fullerene component with channels of alternating fullerenes and carbon disulfide molecules running along the crystallographic b axis. The molecular packing arrangements for D5h-C70·3CS2 and 2(D5h-C70)·3CS2 do not show such channels. In D5h-C70·3CS2, the carbon disulfide molecules form chains that snake between the fullerenes and along the crystallographic a axis. In 2(D5h-C70)·3CS2, there are two crystallographically distinct fullerene cages, which are segregated into individual layers. Within each layer, the fullerenes show hexagonal close packing and the carbon disulfide molecules form chains that snake between the fullerene layers in a zigzag fashion. The presence of diiodine in solution was essential for the formation of crystals of D5h-C70·3CS2 and 2(D5h-C70)·3CS2 that were suitable for structure determination, although no diiodine was incorporated in these crystals.

A single crystal X-ray diffraction study of a fully ordered cocrystal of pristine Sc3N@D3h(5)–C78

Co-reporter:Brandon Q. Mercado, Manuel N. Chaur, Luis Echegoyen, Jafar Attar Gharamaleki, Marilyn M. Olmstead, Alan L. Balch

Polyhedron 2013 58() pp: 129-133

Publication Date(Web):

DOI:10.1016/j.poly.2012.08.035

Azide Addition to an Endohedral Metallofullerene: Formation of Azafulleroids of Sc3N@Ih-C80

Co-reporter:Tong-Xin Liu ; Tao Wei ; San-E Zhu ; Guan-Wu Wang ; Mingzhi Jiao ; Shangfeng Yang ; Faye L. Bowles ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society 2012 Volume 134(Issue 29) pp:11956-11959

Publication Date(Web):July 12, 2012

DOI:10.1021/ja305446v

The reaction of an organic azide with an endohedral metallofullerene has been investigated for the first time. Isomeric [5,6]- and [6,6]-azafulleroids can be obtained from the thermal reaction of Sc3N@Ih-C80 with 4-isopropoxyphenyl azide, while photoirradiation leads exclusively to the [6,6]-azafulleroid. An unprecedented thermal interconversion between the two isomeric azafulleroids has also been discovered.

Isolation of Three Isomers of Sm@C84 and X-ray Crystallographic Characterization of Sm@D3d(19)-C84 and Sm@C2(13)-C84

Co-reporter:Hua Yang ; Meilan Yu ; Hongxiao Jin ; Ziyang Liu ; Mingguang Yao ; Bingbing Liu ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society 2012 Volume 134(Issue 11) pp:5331-5338

Publication Date(Web):February 14, 2012

DOI:10.1021/ja211785u

Three isomers with the composition Sm@C84 were isolated from carbon soot obtained by electric arc vaporization of carbon rods doped with Sm2O3. These isomers were labeled Sm@C84(I), Sm@C84(II), and Sm@C84(III) in order of their elution times during chromatography on a Buckyprep column with toluene as the eluent. Analysis of the structures by single-crystal X-ray diffraction on cocrystals formed with NiII(octaethylporphyrin) reveals the identities of two of the isomers: Sm@C84(I) is Sm@C2(13)-C84, and Sm@C84(III) is Sm@ D3d(19)-C84. Sm@C84(II) can be identified as Sm@C2(11)-C84 on the basis of the similarity of its UV/vis/NIR spectrum with that of Yb@C2(11)-C84, whose carbon cage has been characterized by 13C NMR spectroscopy. Comparison of the three Sm@C84 isomers identified in this project with two prior reports of the preparation and isolation of isomers of Sm@C84 indicate that five different Sm@C84 isomers have been found and that the source of samarium used for the generation of fullerene soot is important in determining which of these isomers form.

Sc2S@Cs(10528)-C72: A Dimetallic Sulfide Endohedral Fullerene with a Non Isolated Pentagon Rule Cage

Co-reporter:Ning Chen ; Christine M. Beavers ; Marc Mulet-Gas ; Antonio Rodríguez-Fortea ; Elias J. Munoz ; Yu-Yang Li ; Marilyn M. Olmstead ; Alan L. Balch ; Josep M. Poblet ;Luis Echegoyen

Journal of the American Chemical Society 2012 Volume 134(Issue 18) pp:7851-7860

Publication Date(Web):April 21, 2012

DOI:10.1021/ja300765z

A non isolated pentagon rule metallic sulfide clusterfullerene, Sc2S@Cs(10528)-C72, has been isolated from a raw mixture of Sc2S@C2n (n = 35–50) obtained by arc-discharging graphite rods packed with Sc2O3 and graphite powder under an atmosphere of SO2 and helium. Multistage HPLC methods were utilized to isolate and purify the Sc2S@C72. The purified Sc2S@Cs(10528)-C72 was characterized by mass spectrometry, UV–vis–NIR absorption spectroscopy, cyclic voltammetry, and single-crystal X-ray diffraction. The crystallographic analysis unambiguously elucidated that the C72 fullerene cage violates the isolated pentagon rule, and the cage symmetry was assigned to Cs(10528)-C72. The electrochemical behavior of Sc2S@Cs(10528)-C72 shows a major difference from those of Sc2S@Cs(6)-C82 and Sc2S@C3v(8)-C82 as well as the other metallic clusterfullerenes. Computational studies show that the Sc2S cluster transfers four electrons to the C72 cage and Cs(10528)-C72 is the most stable cage isomer for both empty C724– and Sc2S@C72, among the many possibilities. The structural differences between the reported fullerenes with C72 cages are discussed, and it is concluded that both the transfer of four electrons to the cage and the geometrical requirements of the encaged Sc2S cluster play important roles in the stabilization of the Cs(10528)-C72 cage.

Single Samarium Atoms in Large Fullerene Cages. Characterization of Two Isomers of Sm@C92 and Four Isomers of Sm@C94 with the X-ray Crystallographic Identification of Sm@C1(42)-C92, Sm@Cs(24)-C92, and Sm@C3v(134)-C94

Co-reporter:Hongxiao Jin ; Hua Yang ; Meilan Yu ; Ziyang Liu ; Christine M. Beavers ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society 2012 Volume 134(Issue 26) pp:10933-10941

Publication Date(Web):April 26, 2012

DOI:10.1021/ja302859r

Two isomers of Sm@C92 and four isomers of Sm@C94 were isolated from carbon soot obtained by electric arc vaporization of carbon rods doped with Sm2O3. Analysis of the structures by single-crystal X-ray diffraction on cocrystals formed with NiII(octaethylporphyrin) reveals the identities of two of the Sm@C92 isomers: Sm@C92(I), which is the more abundant isomer, is Sm@C1(42)-C92, and Sm@C92(II) is Sm@Cs(24)-C92. The structure of the most abundant form of the four isomers of Sm@C94, Sm@C94(I), is Sm@C3v(134)-C94, which utilizes the same cage isomer as the previously known Ca@C3v(134)-C94 and Tm@C3v(134)-C94. All of the structurally characterized isomers obey the isolated pentagon rule. While the four Sm@C90 and five isomers of Sm@C84 belong to common isomerization maps that allow these isomers to be interconverted through Stone–Wales transformations, Sm@C1(42)-C92 and Sm@Cs(24)-C92 are not related to each other by any set of Stone–Wales transformations. UV–vis–NIR spectroscopy and computational studies indicate that Sm@C1(42)-C92 is more stable than Sm@Cs(24)-C92 but possesses a smaller HOMO–LUMO gap. While the electronic structures of these endohedrals can be formally described as Sm2+@C2n2–, the net charge transferred to the cage is less than two due to some back-donation of electrons from π orbitals of the cage to the metal ion.

Single-Crystal X-ray Diffraction Study of Three Yb@C82 Isomers Cocrystallized with NiII(octaethylporphyrin)

Co-reporter:Mitsuaki Suzuki, Zdenek Slanina, Naomi Mizorogi, Xing Lu, Shigeru Nagase, Marilyn M. Olmstead, Alan L. Balch, and Takeshi Akasaka

Journal of the American Chemical Society 2012 Volume 134(Issue 45) pp:18772-18778

Publication Date(Web):October 22, 2012

DOI:10.1021/ja308706d

Single crystals of three soluble Yb@C82 isomers, namely, Yb@C2(5)-C82, Yb@Cs(6)-C82, and Yb@C2v(9)-C82, cocrystallized with NiII(octaethylporphyrin), allowed accurate crystallographic elucidation of their molecular structures in terms of both cage symmetry and metal location. Multiple metal positions were found in all these isomers, but the major metal sites were found in some specific regions within these cages. Specifically, the Yb2+ ion prefers to reside close to a hexagonal ring in Yb@C2(5)-C82 and Yb@C2v(9)-C82 but a [5,6,6]-junction carbon atom in Yb@Cs(6)-C82. Theoretical calculations at the B3LYP level revealed that these metal positions all correspond to energy minima from the electrostatic potential maps and give rise to the most stable configurations of these Yb@C82 isomers. Furthermore, it is noteworthy that this is the first report on X-ray crystallographic studies of such metallofullerenes with the popular C2v(9)-C82 encapsulating a divalent metal ion, described as M2+@[C2v(9)-C82]2–.

Selective Synthesis, Isolation, and Crystallographic Characterization of LaSc2N@Ih-C80

Co-reporter:Steven Stevenson, Coralie B. Rose, Juliya S. Maslenikova, Jimmy R. Villarreal, Mary A. Mackey, Brandon Q. Mercado, Kelly Chen, Marilyn M. Olmstead, and Alan L. Balch

Inorganic Chemistry 2012 Volume 51(Issue 24) pp:13096-13102

Publication Date(Web):December 6, 2012

DOI:10.1021/ic300888e

The successful preparation and isolation of the mixed-metal endohedral fullerene, LaSc2N@Ih-C80, and its structural characterization by single-crystal X-ray diffraction are reported. Results from chemically adjusting plasma temperature, energy, and reactivity (CAPTEAR) experiments indicate that a 10 wt % addition of Cu(NO3)2·2.5H2O to a mixture of La2O3 and Sc2O3 decreases the amount of C60 and C70 found in soot extracts by an order of magnitude. By combining a stoichiometric 2-fold excess of La to Sc atoms in the plasma reactor, an extract containing a greater abundance of LaSc2N@Ih-C80 relative to Sc3N@Ih-C80 was obtained. Alternatively, the stir and filter approach (SAFA method) can be used to remove the empty cage fullerenes from a carbon soot sample prepared without using Cu(NO3)2·2.5H2O. LaSc2N@Ih-C80 has been characterized by UV/vis absorption spectroscopy and by single-crystal X-ray diffraction. Ordered crystals with nearly identical orientations of the endohedral relative to the porphyrin have been obtained by cocrystallization of LaSc2N@Ih-C80 with either NiII(OEP) or H2(OEP). The LaSc2N unit is planar, although earlier computations suggested that it would be pyramidal.

Isolation of Four Isomers of C96 and Crystallographic Characterization of Nanotubular D3d(3)-C96 and the Somewhat Flat-Sided Sphere C2(181)-C96

Co-reporter:Hua Yang;Hongxiao Jin;Yuliang Che;Bo Hong;Dr. Ziyang Liu;Dr. Jafar Attar Gharamaleki;Dr. Marilyn M. Olmstead;Dr. Alan L. Balch

Chemistry - A European Journal 2012 Volume 18( Issue 10) pp:2792-2796

Publication Date(Web):

DOI:10.1002/chem.201103852

Isolation and Crystallographic Identification of Four Isomers of Sm@C90

Co-reporter:Hua Yang ; Hongxiao Jin ; Hongyu Zhen ; Zhimin Wang ; Ziyang Liu ; Christine M. Beavers ; Brandon Q. Mercado ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society 2011 Volume 133(Issue 16) pp:6299-6306

Publication Date(Web):March 31, 2011

DOI:10.1021/ja111465n

Four isomers with the composition SmC90 were obtained from carbon soot produced by electric arc vaporization of carbon rods doped with Sm2O3. These were labeled Sm@C90(I), Sm@C90(II), Sm@C90(III), and Sm@C90(IV) in order of their elution times during chromatography on a Buckyprep column with toluene as the eluent. Analysis of the structures by single-crystal X-ray diffraction on cocrystals formed with Ni(octaethylporphyrin) reveals the identities of the individual isomers as follows: I, Sm@C2(40)-C90; II, Sm@C2(42)-C90; III, Sm@C2v(46)-C90 and IV, Sm@C2(45)-C90. This is the most extensive series of isomers of any endohedral fullerene to have their individual structures determined by single-crystal X-ray diffraction. The cage structures of these four isomers can be related pairwise to one another in a formal sense through sequential Stone−Wales transformations.

Very Large, Soluble Endohedral Fullerenes in the Series La2C90 to La2C138: Isolation and Crystallographic Characterization of La2@D5(450)-C100

Co-reporter:Christine M. Beavers ; Hongxiao Jin ; Hua Yang ; Zhimin Wang ; Xinqing Wang ; Hongliang Ge ; Ziyang Liu ; Brandon Q. Mercado ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society 2011 Volume 133(Issue 39) pp:15338-15341

Publication Date(Web):August 24, 2011

DOI:10.1021/ja207090e

An extensive series of soluble dilanthanum endohedral fullerenes that extends from La2C90 to La2C138 has been discovered. The most abundant of these, the nanotubular La2@D5(450)-C100, has been isolated in pure form and characterized by single-crystal X-ray diffraction.

Large Endohedral Fullerenes Containing Two Metal Ions, Sm2@D2(35)-C88, Sm2@C1(21)-C90, and Sm2@D3(85)-C92, and Their Relationship to En

Co-reporter:Hua Yang, Hongxiao Jin, Bo Hong, Ziyang Liu, Christine M. Beavers, Hongyu Zhen, Zhimin Wang, Brandon Q. Mercado, Marilyn M. Olmstead, and Alan L. Balch

Journal of the American Chemical Society 2011 Volume 133(Issue 42) pp:16911-16919

Publication Date(Web):September 14, 2011

DOI:10.1021/ja206244w

The carbon soot obtained by electric arc vaporization of carbon rods doped with Sm2O3 contains a series of monometallic endohedral fullerenes, Sm@C2n, along with smaller quantities of the dimetallic endohedrals Sm2@C2n with n = 44, 45, 46, and the previously described Sm2@D3d(822)-C104. The compounds Sm2@C2n with n = 44, 45, 46 were purified by high pressure liquid chromatography on several different columns. For endohedral fullerenes that contain two metal atoms, there are two structural possibilities: a normal dimetallofullerene, M2@C2n, or a metal carbide, M2(μ-C2)@C2n–2. For structural analysis, the individual Sm2@C2n endohedral fullerenes were cocrystallized with Ni(octaethylporphyrin), and the products were examined by single-crystal X-ray diffraction. These data identified the three new endohedrals as normal dimetallofullerenes and not as carbides: Sm2@D2(35)-C88, Sm2@C1(21)-C90, and Sm2@D3(85)-C92. All four of the known Sm2@C2n endohedral fullerenes have cages that obey the isolated pentagon rule (IPR). As the cage size expands in this series, so do the distances between the variously disordered samarium atoms. Since the UV/vis/NIR spectra of Sm2@D2(35)-C88 and Sm2@C1(21)-C90 are very similar to those of Gd2C90 and Gd2C92, we conclude that Gd2C90 and Gd2C92 are the carbides Gd2(μ-C2)@D2(35)-C88 and Gd2(μ-C2)@C1(21)-C90, respectively.

[2 + 2] Cycloaddition Reaction to Sc3N@Ih-C80. The Formation of Very Stable [5,6]- and [6,6]-Adducts

Co-reporter:Fang-Fang Li ; Julio R. Pinzón ; Brandon Q. Mercado ; Marilyn M. Olmstead ; Alan L. Balch ;Luis Echegoyen

Journal of the American Chemical Society 2011 Volume 133(Issue 5) pp:1563-1571

Publication Date(Web):January 10, 2011

DOI:10.1021/ja1097176

The [2 + 2] cycloaddition reaction of Sc3N@Ih-C80 with benzyne was successfully conducted for the first time. The reaction affords both the [5,6]- and [6,6]-monoadducts with a four-membered ring attached to the cage surface on 5,6- and 6,6-ring fusions, respectively. The compounds were characterized by MALDI-TOF, NMR, UV−vis−NIR spectroscopy and single-crystal X-ray structure determination. The electrochemical behavior of both monoadducts was investigated. The [5,6]-regioisomer displays reversible cathodic behavior similar to that observed for the fulleropyrrolidines with a 5,6-addition pattern. Surprisingly, the [6,6]-regioisomer also exhibits reversible cathodic behavior. The interconversion reaction of the isomers was also explored, and the results showed that both monoadducts are thermally very stable.

Fullerenes without symmetry: crystallographic characterization of C1(30)–C90 and C1(32)–C90

Co-reporter:Hua Yang, Brandon Q. Mercado, Hongxiao Jin, Zhimin Wang, An Jiang, Ziyang Liu, Christine M. Beavers, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2011 vol. 47(Issue 7) pp:2068-2070

Publication Date(Web):07 Dec 2010

DOI:10.1039/C0CC03017A

Fullerenes are generally considered as highly symmetric, yet fullerene isomers with only C1 symmetry, such as C1(30)–C90 and C1(32)–C90 whose structures are reported here, become increasingly numerous as fullerene size increases.

The Cycloaddition Reaction of Ih-Sc3N@C80 with 2-Amino-4,5-diisopropoxybenzoic Acid and Isoamyl Nitrite to Produce an Open-Cage Metallofullerene

Co-reporter:Dr. Guan-Wu Wang;Tong-Xin Liu;Mingzhi Jiao;Nan Wang;San-E Zhu;Chuanbao Chen;Dr. Shangfeng Yang;Faye L. Bowles;Dr. Christine M. Beavers;Dr. Marilyn M. Olmstead;Bron Q. Mercado;Dr. Alan L. Balch

Angewandte Chemie International Edition 2011 Volume 50( Issue 20) pp:4658-4662

Publication Date(Web):

DOI:10.1002/anie.201100510

Co-reporter:Zhimin Wang, Hua Yang, An Jiang, Ziyang Liu, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2010 vol. 46(Issue 29) pp:5262-5264

Publication Date(Web):10 Jun 2010

DOI:10.1039/C0CC00697A

We report an analysis of the similar structures of Cs(16)-C86 and C2(17)-C86 from a single crystal X-ray diffraction study of Cs(16)/C2(17)-C86·(nickel octaethylporphyrin)·2toluene.

A seven atom cluster in a carbon cage, the crystallographically determined structure of Sc4(μ3-O)3@Ih-C80

Co-reporter:Brandon Q. Mercado, Marilyn M. Olmstead, Christine M. Beavers, Michael L. Easterling, Steven Stevenson, Mary A. Mackey, Curtis E. Coumbe, Joshua D. Phillips, J. Paige Phillips, Josep M. Poblet and Alan L. Balch

Chemical Communications 2010 vol. 46(Issue 2) pp:279-281

Publication Date(Web):09 Nov 2009

DOI:10.1039/B918731F

The tetrahedral array of four scandium atoms with oxygen atoms capping three of the four faces found in Sc4(μ3-O)3@Ih-C80 is the largest cluster isolated to date inside a fullerene cage.

New Tetraazaannulene Hosts for Fullerenes

Co-reporter:Jimmy U. Franco, Justin C. Hammons, Daniel Rios and Marilyn M. Olmstead

Inorganic Chemistry 2010 Volume 49(Issue 11) pp:5120-5125

Publication Date(Web):May 4, 2010

DOI:10.1021/ic1002513

Two modifications to the doubly concaved host molecules based on well-known nickel tetraazaannulene complexes have resulted in the preparation of the compounds Ni(NapTMTAA)·2benzene, 1,6,8,15,17-tetramethyldinapthalene-5,9,14,18-tetraazacyclotetradecinatonickel(II), and Ni(Cl4TMTAA)·CH2Cl2, 2,3,11,12-tetrachloro-6,8,15,17-tetramethyldibenzo-5,9,14,18-tetraazacyclotetradecinatonickel(II). When crystallized with C60 in carbon disulfide, the crystalline, well-ordered, host−guest compounds Ni(NapTMTAA)·C60·2CS2 and Ni(Cl4TMTAA)·C60·2CS2 were formed. The compounds were characterized by X-ray crystallography. The crystal structures of the precursor host molecules showed very strong host−host interactions, particularly in the case of Ni(Cl4TMTAA), which had short Ni···Ni interactions of 3.3860(11) and 3.5888(11) Å in the two different dimers in the asymmetric unit; yet, these host−host interactions were entirely destroyed in the resultant host−guest compounds, and C60 molecules were shown to make use of both cusps of the host macrocycle in the formation of a shape-selective arrangement.

Isolation of a Small Carbon Nanotube: The Surprising Appearance of D5h(1)-C90

Co-reporter:Hua Yang;ChristineM. Beavers Dr.;Zhimin Wang;An Jiang;Ziyang Liu Dr.;Hongxiao Jin Dr.;BronQ. Mercado;MarilynM. Olmstead Dr.;AlanL. Balch Dr.

Angewandte Chemie International Edition 2010 Volume 49( Issue 5) pp:886-890

Publication Date(Web):

DOI:10.1002/anie.200906023

Large Metal Ions in a Relatively Small Fullerene Cage: The Structure of Gd3N@C2(22010)-C78 Departs from the Isolated Pentagon Rule

Co-reporter:Christine M. Beavers ; Manuel N. Chaur ; Marilyn M. Olmstead ; Luis Echegoyen ;Alan L. Balch

Journal of the American Chemical Society 2009 Volume 131(Issue 32) pp:11519-11524

Publication Date(Web):July 14, 2009

DOI:10.1021/ja903741r

An isomerically pure sample of Gd3N@C78 has been extracted from the carbon soot formed in the electric-arc generation of fullerenes using hollow graphite rods packed with Gd2O3 and graphite powder under an atmosphere of helium and dinitrogen. Purification has been achieved by chromatographic methods and the product has been characterized by mass spectrometry, UV/vis absorption spectroscopy, and cyclic voltammetry. Although a number of endohedral fullerenes have been found to utilize the D3h(5)-C78 cage, comparison of the spectroscopic and electrochemical properties of the previously characterized Sc3N@D3h(5)-C78 with those of Gd3N@C78 reveals significant differences that indicate that these two endohedrals do not possess the same cage structure. A single crystal X-ray diffraction study indicates that the fullerene cage does not follow the isolated pentagon rule (IPR) but has two equivalent sites where two pentagons abut. The endohedral has been identified as Gd3N@C2(22010)-C78. Two of the gadolinium atoms of the planar Gd3N unit are located within the pentalene folds formed by the adjacent pentagons. The third gadolinium atom resides at the center of a hexagonal face of the fullerene.

Tetragonal to Triclinic—A Phase Change for [Fe(TPP)(NO)]

Co-reporter:Nathan J. Silvernail ; Marilyn M. Olmstead ; Bruce C. Noll ;W. Robert Scheidt

Inorganic Chemistry 2009 Volume 48(Issue 3) pp:971-977

Publication Date(Web):January 7, 2009

DOI:10.1021/ic801617q

The temperature dependence of the crystalline phase of (nitrosyl)(tetraphenylporphinato)iron(II), [Fe(TPP)(NO)], has been explored over the temperature range of 33−293 K. The crystalline complex is found in the tetragonal crystal system at higher temperatures and in the triclinic crystal system at lower temperatures. In the tetragonal system, the axial ligand is strongly disordered, with the molecule having crystallographically required 4/m symmetry, leading to eight distinct positions of the single nitrosyl oxygen atom. The phase transition to the triclinic crystal system leads to a partial ordering with the molecule now having inversion symmetry and disorder of the axial nitrosyl ligand over only two positions. The increase in ordering allows subtle molecular geometry features to be observed; in particular, an off-axis tilt of the Fe−NNO bond from the heme normal is apparent. The transition of the reversible phase change begins at about 250 K. This transition has been confirmed by both X-ray diffraction studies and a differential scanning calorimetry study.

Isolation and Structural Characterization of Two Very Large, and Largely Empty, Endohedral Fullerenes: Tm@C3v-C94 and Ca@C3v-C94

Co-reporter:Yuliang Che, Hua Yang, Zhimin Wang, Hongxiao Jin, Ziyang Liu, Chunxin Lu, Tianming Zuo, Harry C. Dorn, Christine M. Beavers, Marilyn M. Olmstead and Alan L. Balch

Inorganic Chemistry 2009 Volume 48(Issue 13) pp:6004-6010

Publication Date(Web):June 9, 2009

DOI:10.1021/ic900322d

The structures of two newly synthesized endohedral fullerenes, Tm@C3v-C94 and Ca@C3v-C94, have been determined by single crystal X-ray diffraction on samples cocrystallized with NiII(octaethylporphyrin). Both compounds exhibit the same cage geometry and conform to the isolated pentagon rule (IPR). The metal ions within these rather large cages are localized near one end and along the C3 axis. While the calcium ion is situated over a C−C bond at a 6:6 ring junction, the thulium ion is positioned above a six-membered ring of the fullerene.

Formation of Crystalline Polymers from the Reaction of Amine-Functionalized C60 with Silver Salts

Co-reporter:Christopher J. Chancellor ; Marilyn M. Olmstead ;Alan L. Balch

Inorganic Chemistry 2009 Volume 48(Issue 4) pp:1339-1345

Publication Date(Web):January 9, 2009

DOI:10.1021/ic8012427

Three new crystalline compounds of Ag(I) with fullerene-containing ligands, the piperidine adduct [C60(N(CH2CH2)2N)] and the fullero[60]pyrrolidine [C60(CH2N(CH3)CH2)], have been prepared and characterized by X-ray crystallography. The polymeric structure of {[C60(N(CH2CH2)2N)][Ag(O2CCF3)]2}·CS2 consists of linear chains composed of two distinct molecules of the functionalized fullerene, with four Ag(I) ions attached to the four nitrogen atoms and four bridging trifluoroacetate ions. Two of the four Ag(I) ions form η2-bonds to carbon atoms in different regions of the fullerene cage, and there is one close Ag−Ag contact (3.1657(7) Å) as well. These chains are further cross-linked by bridging trifluoroacetate ions. The structure of {[C60(CH2N(CH3)CH2)]Ag(NO3)}·0.25CH3OH involves two similar polymeric chains in which Ag(I) ions bind to the nitrogen atom of one N-methyl-3,4-fullero[60]pyrrolidine ligand and to a carbon atom of another N-methyl-3,4-fullero[60]pyrrolidine in η1-fashion for one chain and in distorted η2-fashion in the other. Additionally, each Ag(I) ion is bonded to two oxygen atoms from two bridging nitrate ions. On the other hand, [C60(N(CH2CH2)2N)]2Ag(NO3)·0.5CH3OH·CH2Cl2 is a simple coordination complex with two very large ligands attached to Ag(I). Coordination of Ag(I) to C60 produces much smaller alterations to the fullerene geometry than does coordination of Pt0(PPh3)2 or IrI(CO)Cl(PPh3)2 groups.

Crystal Packing in Planar Platinum(II) and Palladium(II) Complexes. Hydrogen-Bond-Mediated Supramolecular Assembly of Ten Wedge-Shaped Molecules into a Cyclic Array

Co-reporter:Emily M. Gussenhoven, Martyn Jevric, Marilyn M. Olmstead, James C. Fettinger, Mark Mascal and Alan L. Balch

Crystal Growth & Design 2009 Volume 9(Issue 4) pp:1786-1792

Publication Date(Web):February 25, 2009

DOI:10.1021/cg800906x

The molecular packing arrangements for the unsolvated compounds, PtCl2(ATQ-CH2NH2) (1a) and PdCl2(ATQ-CH2NH2) (2) (ATQ = azatriquinane), and two solvates of the platinum complex, 6{PtCl2(ATQ-CH2NH2)}·2(CH3CN) (1b) and 3{PtCl2(ATQ-CH2NH2)}·2(CH2Cl2) (1c), are reported. These planar, d8 complexes have a wedgelike shape due to the presence of the bulky azatriquinane unit coordinated directly to the metal. All of the crystals exhibit hydrogen bonding between the N−H groups of one molecule and the chloride ligands on another. Despite the similar sizes and shapes of the complexes, the unsolvated compounds, PtCl2(ATQ-CH2NH2) (1a) and PdCl2(ATQ-CH2NH2) (2), pack in entirely different fashions, with metallophilic interactions between pairs of cofacial complexes in the palladium complex. The platinum complex lacks the metallophillic interactions. The structure of 6{PtCl2(ATQ-CH2NH2)}·2(CH3CN) (1b) is noteworthy for two features. First, these crystals contain an ordered cyclic assembly of 10 molecules of the complex with all the Pt−Cl groups directed toward the inside of the ring. The formation of this supramolecular macrocyclic array is facilitated by extensive hydrogen bonding between the NH groups of one molecule and the chloride ligands of another. Second, these crystals also contain a poorly organized region where one PtCl2(ATQ-CH2NH2) molecule is disordered over several orientations. 3{PtCl2(ATQ-CH2NH2)}·2(CH2Cl2) (1c) crystallizes with three molecules of the platinum complex in a crescent-shaped array that shows some similarity with the cyclic structure found in 6{PtCl2(ATQ-CH2NH2)}·2(CH3CN) (1b).

Isolation and Structural Characterization of the Molecular Nanocapsule Sm2@D3d(822)-C104

Co-reporter:BronQ. Mercado;An Jiang;Hua Yang;Zhimin Wang;Hongxiao Jin;Ziyang Liu Dr.;MarilynM. Olmstead Dr.;AlanL. Balch Dr.

Angewandte Chemie International Edition 2009 Volume 48( Issue 48) pp:9114-9116

Publication Date(Web):

DOI:10.1002/anie.200904662

Co-reporter:Hua Yang ; Hongxiao Jin ; Xinqing Wang ; Ziyang Liu ; Meilan Yu ; Fukun Zhao ; Brandon Q. Mercado ; Marilyn M. Olmstead ;Alan L. Balch

Journal of the American Chemical Society () pp:

Publication Date(Web):August 3, 2012

DOI:10.1021/ja304867j

Fullerenes without symmetry: crystallographic characterization of C1(30)–C90 and C1(32)–C90

Co-reporter:Hua Yang, Brandon Q. Mercado, Hongxiao Jin, Zhimin Wang, An Jiang, Ziyang Liu, Christine M. Beavers, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2011 - vol. 47(Issue 7) pp:NaN2070-2070

Publication Date(Web):2010/12/07

DOI:10.1039/C0CC03017A

Co-reporter:Zhimin Wang, Hua Yang, An Jiang, Ziyang Liu, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2010 - vol. 46(Issue 29) pp:NaN5264-5264

Publication Date(Web):2010/06/10

DOI:10.1039/C0CC00697A

We report an analysis of the similar structures of Cs(16)-C86 and C2(17)-C86 from a single crystal X-ray diffraction study of Cs(16)/C2(17)-C86·(nickel octaethylporphyrin)·2toluene.

A seven atom cluster in a carbon cage, the crystallographically determined structure of Sc4(μ3-O)3@Ih-C80

Chemical Communications 2010 - vol. 46(Issue 2) pp:NaN281-281

Publication Date(Web):2009/11/09

DOI:10.1039/B918731F

The tetrahedral array of four scandium atoms with oxygen atoms capping three of the four faces found in Sc4(μ3-O)3@Ih-C80 is the largest cluster isolated to date inside a fullerene cage.

Orientational variation, solvate composition and molecular flexibility in well-ordered cocrystals of the fullerene C70 with bis(ethylenedithio)tetrathiafulvalene

Co-reporter:Kamran B. Ghiassi, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2013 - vol. 49(Issue 91) pp:NaN10723-10723

Publication Date(Web):2013/10/04

DOI:10.1039/C3CC46367B

Zipping up fullerenes into polymers using rhodium(II) acetate dimer and N(CH2CH2)2NC60 as building blocks

Co-reporter:Amineh Aghabali, Marilyn M. Olmstead and Alan L. Balch

Chemical Communications 2014 - vol. 50(Issue 96) pp:NaN15155-15155

Publication Date(Web):2014/10/16

DOI:10.1039/C4CC06995A

The reaction of Rh2(O2CCH3)4 with the functionalized fullerene N(CH2CH2)2NC60 can produce a linear, crystalline polymer or can trap free C60 or C70 molecules between similar chains.