Interaction of platinum fulleride C60Pt with deuterium

X-ray photoelectron spectra and catalytic properties of platinum fulleride C₆₀Pt were studied. The value of the bond energy of Pt4f_7/2 (72.4 eV) found for platinum in the starting C₆₀Pt suggests a partial charge transfer from Pt to C₆₀. The interaction of solid platinum fulleride with gaseous deuterium leads to the formation of fullerene deuterides C₆₀D _x and Pt clusters. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 999–1002, May, 1999.     

C60Pd（Ph2POCH2CH2OPPh2）的合成与光电转化性能

C60Pd（Ph2POCH2CH2OPPh2）的合成与光电转化性能;富勒烯;钯配合物;光电性能     

Reaction of fullerene C60 with 2-azido-4,6-diphenylpyrimidine

The first representative of the pyrimidine-substituted [60]fullereno[1,2-b]aziridines was synthesized by the reaction of fullerene C₆₀ with 2-azido-4,6-diphenylpyrimidine. 2-(Azahomo[60]fullereno)-4,6-diphenylpyrimidine was found to be formed as a by-product. The electrochemical properties of the adducts were studied.     

C60与叠氮化合物的单加成反应

本文从实验以及理论研究两方面介绍了C60与叠氧化合物的单加成反应。依照叠氮化合物的不同,C60与叠氮合物的单加成反应可分为烷基叠氮化物与C60的反应,酰基叠氧化物与C60的反应以及苯基叠氮化与C60的反应三类,而反应产物则为C60亚氨基[6,6]闭环衍生物和C60亚氨基[5,6]开环衍生物两类,不同类型的反应具有不同的反应机理,某些C60亚氨基[5,6]开环衍生物可以转化为C60亚氨基[6,6]闭环衍生物。本文还介绍了碳纳米管与叠氮化合物的加成反应。     

C60负离子与1,2-二溴丁二酸钠的高选择性加成反应与生物活性研究

研究了在四氢呋喃溶液中,C60^2-负离子与1,2-二溴丁二酸钠的反应,制得水溶性的衍生物,通过FD-MS．^1HNMR,FT—IR,UV-vis等多种波谱技术对衍生物结构进行了表征,认为该反应为高选择性加成反应;通过衍生物的生物活性实验,证明该衍生物对正常细胞无毒副作用,而对大肠杆菌生长有抑制作用,在5,10μL浓度下表现出对肝癌细胞生长具有弱的抑制作用,证明该衍生物在抑制真菌生长药物和治疗肿瘤药物方面有潜在的应用价值．     

Mass spectrometric study of the ionized C60: (gamma-Cyclodextrin)2 inclusion complex by collision induced dissociation

The water soluble inclusion complex [C(60):(gamma-cyclodextrin)(2)] has been characterized using electrospray tandem mass spectrometry and collision induced dissociation. [C(60):(gamma-cyclodextrin)(2)] ions were detected in the gas phase as doubly deprotonated, doubly protonated and doubly sodiated ions. The absence of monocharged complex ions following electronebulization is a likely consequence of the dimeric nature and structural symmetry of the inclusion complex. The collision induced dissociation of positive ions led exclusively to the observation of the protonated and sodiated cyclodextrin ions as well as their fragments. In negative ion mode the closed shell anion C(60)H(-) was the dominant fragment detected at low collision energies whereas at higher collision energies the signal corresponding to deprotonated cyclodextrin units becomes significant. Since C(60) (2-) has been reported to have a nonnegligible basicity compared to C(60) and C(60) (-), it is likely that the proton transfer involved in the formation of the C(60)H(-) anion occurs following transfer of the two electrons from the deprotonated gamma-cyclodextrins to the fullerene. Finally, the charge state of the inclusion complex ions is also shown to affect the interaction strengths between its subunits. The relative stabilities of the three ionic species studied in gas phase following electronebulization are as follows: [C(60):(gamma-cyclodextrin)(2) + 2H](2+) < [C(60):(gamma-cyclodextrin)(2)- 2H](2-) < [C(60):(gamma-cyclodextrin)(2) + 2Na](2+).     

Trinuclear Pd3O2 Intermediate in Aerobic Oxidation Catalysis

The activation of O₂ is a key step in selective catalytic aerobic oxidation reactions mediated by transition metals. The bridging trinuclear palladium species, [(LPd^II)₃(μ³‐O)₂]²⁺ (L=2,9‐dimethylphenanthroline), was identified during the [LPd(OAc)]₂(OTf)₂‐catalyzed aerobic oxidation of 1,2‐propanediol. Independent synthesis, structural characterization, and catalytic studies of the trinuclear compound show that it is a product of oxygen activation by reduced palladium species and is a competent intermediate in the catalytic aerobic oxidation of alcohols. The formation and catalytic activity of the trinuclear Pd₃O₂ species illuminates a multinuclear pathway for aerobic oxidation reactions catalyzed by Pd complexes.     

Structure of palladium quinoline-8-selenolate Pd(C9H6NSe)2

The molecular and crystal structure of palladium quinoline-8-selenolate Pd(C₉H₆NSe)₂ has been determined by X-ray structural analysis. The structures of the five-membered metallocycles of palladium 8-hydroxy-, 8-mercapto-, and 8-hydroselenoquinolinates of one type are compared. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 396–402, March, 2006.     

Mass spectrometric characterization of 3'-imino[60]fulleryl-3'-deoxythymidine by collision-induced dissociation

The primary structure of 3'-imino[60]fulleryl-3'-deoxythymidine ions is studied using mass spectrometry both in the positive and negative modes. Interaction between the subunits is discussed using collision-induced dissociation (CID) spectra. Collisional activation with argon of the sodiated cations leads to the cleavage of the glycosidic bond and the transfer of a radical hydrogen from the deoxyribose to the thymine. The sodiated thymine is the only fragment observed for low collision energies in the positive mode. In the negative mode, two different ionization mechanisms take place, reduction and deprotonation in the presence of triethylamine. The 2.7 eV electron affinity of C60 and its huge cross section compared to the small cross section and predicted 0.44 eV electron affinity of the thymidine subunit most likely localize the radical electron on the fullerene. On the other hand, deprotonation of the 3'-azido-3'-deoxythymidine (AZT) is known to occur in N-3, the most acidic site of the nucleobase. Consequently, deprotonation causes the negative charge to be initially localized on the thymine. Both types of parent anions give the radical anion C60*- as fragment. The other fragments detected are the dehydrogenated 3'-imino[60]fulleryl-3'-deoxyribose anion, C60NH2-, C60N- and C60H-. Since in negative ion mass spectrometry all fragments include the [60]fullerene unit, this suggests that the fragmentation is driven by the electron affinity of the [60]fullerene, likely responsible for a charge transfer between the deprotonated thymine and the C60.     

Crystal solvate of C60 with tricloroethylene,C60 · C2HCl3

Extraction of fullerenes from carbon soot by trichloroethylene has been studied. We have found that C₆₀ forms a solvate with trichloroethylene (C₆₀ · C₂HCl₃:a=31.31(1);b= 10.156(4);c=10.146(4) Å;V=3228.6 ų,Z=4,d _calc=1.752 g cm^–3, orthorhombic symmetry). Its thermal stability has been studied using TG and DSC. A phase transition of the first order at 167 K has been detected.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1248–1250, July, 1994.The authors are grateful to V. P. Bubnov and I. S. Krainskii for providing them with the samples of fulle-rene-containing carbon soot, and to M. G. Kaplunov and A. V. Zvarykina for assistance in the work.This work was carried out with the financial support of the Russian Foundation for Basic Research, Project Nos. 93-03-18705 and 93-03-5650.     

Synthesis of a New Cavitand. 2 C60 Complex

Abstract

A new cavitand 2 and its complexation with fullerene to afford complex 3 was prepared and characterized by spectroscopic methods. Macrocycle 2 was studied in solution by NMR, and in the solid state by ¹³C CP-MAS, NMR and X-ray diffraction. The macrocycle 2 can host 2 fullerene C₆₀ molecules in its structure. For the complex 3, π-π, CH-π and n-π interactions were observed by ¹³C CP-MAS and FTIR spectroscopy. MM and MD calculations were carried out.     

Marriage of Heterobuckybowls with Triptycene: Molecular Waterwheels for Separating C60 and C70

Exploration of π-conjugated polycycles, particularly those have π-frameworks spread over the three-dimensional space, is essential in materials science and synthetic chemistry as these chemical entities possess featured optoelectronic properties and supramolecular assembly. Herein, the bowl-shaped trichalcogenasumanenes are fused onto three branches of triptycene through pyrazine units, affording waterwheel-like three-dimensional polycycles 4 a/4 b . Because the three branches on 4 a/4 b are chemically equal, the molecular orbitals of 4 a/4 b show degenerate feature that results in the strong UV-Vis absorbance at steady state. 4 a/4 b exhibit photo-induced charge-separation and subsequent charge-redistribution at transient state, leading to excited state absorption in NIR-II window (1165–1400 nm). 4 a/4 b are excellent fullerene receptors, and they form 1 : 1 host-guest complexes with C₆₀/C₇₀ as proved by spectroscopic titrations and single crystal structure analysis. Moreover, 4 a/4 b show much stronger affinity toward C₇₀ than C₆₀. Consequently, 4 a/4 b are able to separate C₆₀ and C₇₀ from their mixture, giving the purity of C₆₀ up to 99.5 %.     

活性碳分离碳—60和碳—70

活性碳用苯胺处理后，可以减少对Ｃ６０和Ｃ７０的不可逆吸附，从而增加Ｃ６０和Ｃ７０的分离收率，同时提高了Ｃ７０的纯度。     

Interaction of fullerene C60 with 3-amino-1-propanol

The C₆₀ radical anions formed in the interaction of c₆₀ with 3-amino-1-propanol under a vacuum were characterized by ESR and near-IR spectroscopy. in the air, a compound was obtained whose composition corresponds to the C₆₀NH₂CH₂CH₂CH₂OH=13.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1145, June, 1994.We thank the Russian Foundation for Basic Research (Grant No. 93-03-18001) for financial support.     

Induced Absorption of C60 and a Water-Soluble C60-Derivative in SiO2 Sol-Gel Matrices

Porous sol-gel glasses, either impregnated with pure C₆₀ or doped with a methanofullerene derivative, have been studied and induced absorption or reverse saturable absorption (RSA) has been observed in both types of solid materials. The samples impregnated by pure C₆₀ mainly contain well-dispersed fullerene molecules. Unlike crystalline films of C₆₀, their absorption dynamics can be well described by a 5-level model, developed for non-interacting C₆₀-molecules in solutions. Methanofullerene samples, on the other hand, show signs of micellar aggregation and therefore RSA dynamics that are influenced by solid state effects. We observe an important decrease of transmission at high fluences for both kinds of samples, a shortened singlet-state lifetime to that observed in solution, but nonetheless, a triplet yield, that cannot be considered as negligible. In the case of pure C₆₀ in a sol-gel matrix, we can explain the faster de-excitation dynamics, relative to behavior in solution, mainly by the absence of stabilizing aromatic solvents and also by the interaction of the amorphous environment with the molecules. Concerning the methanofullerene samples, the acceleration of the de-excitation dynamics can be principally attributed to solid-state effects due to the micellar aggregation.     

Mass spectrometry of polyaromatic sulfur compounds in the presence of palladium(II)

Electrospray ionization mass spectrometry (ESI-MS) and tandem MS in an ion trap were used to explore the reduction of a PdCl(2) solution and the role of the metal in the formation of organosulfur radical cations. For tandem MS experiments, a 32 Da neutral loss (M - S), was observed for dibenzothiophene, thianthrene and benzonaphthothiophene, whereas both 32 and 33 Da neutral losses were observed for 2-methyldibenzothiophene and 4,6-dimethyldibenzothiophene. The effects of several variables on the formation of molecular ions or molecular fragments were studied to optimize radical cation formation, including the concentration ratio between PdCl(2) and sulfur and the collision energy. Electrochemical and chromatographic data were used to provide an explanation for the relative sensitivity observed for a mixture of polyaromatic sulfur heterocycles.     

Reactions of C60 with Pyridazine and Phthalazine

Cage-opened bisfulleroids are one of suitable building blocks for making a large hole on fullerenes. This work focuses on the Diels-Alder reaction of C₆₀ with azines, among synthetic methods developed thus far, to provide bisfulleroids. Surprisingly, the computational study predicted that the reaction proceeds with normal electron demand in contrast to hitherto considered inverse-electron-demand pathway. The benzoannulation to the pyridazine ring, i. e., phthalazine, resulted in the remarkably shortened reaction time due to the better interaction between the HOMO of phthalazine and the LUMO of C₆₀ as well as stronger 2,3-diaza-1,3-butadiene character in the phthalazine as confirmed crystallographically. Contrary to expectations, the benzobisfulleroid was converted into corresponding orifice-enlarged derivative via the photooxygenation slightly faster than the fulleroid derived from pyridazine.