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The formation of secondary fullerene ozonides (SFOs) in the ozonolysis of C60 solutions in CCl4 has reliably been determined for the first time; SFOs are accumulated during the whole ozonolysis time as a suspension in CCl4. Hydrolysis of the SFOs results in chemiluminescence (CL) ( I max = 2.65·108 photon s−1 mL−1), whose spectra contain maxima at 558, 608, and 685 nm. The most probable CL emitters are excited fullerene polyketones. Hydrogen peroxide was identified as a stable hydrolysis product of the SFOs by the color reaction with diphenylcarbazide and CL arisen upon the addition of an aqueous solution of FeSO4·9H2O to the hydrolyzate of the SFO. Chemiluminescence upon hydrolysis is a selective test for SFOs and allows one to find them in a complex mixture of the ozonolysis products of C60. The rate constant and activation energy of SFO hydrolysis were determined from the kinetic measurements of CL. For SFO hydrolysis several probable reactions were proposed, including the formation of the CL emitters, and their heat effects were estimated using the PM3/RHF and AM1/RHF semiempirical methods for one-and two-cage model structures of SFOs. [ABSTRACT FROM AUTHOR]

Quenching of electronically excited states of Ln3+* ions generated upon photoexcitation of toluene solutions of Ln(acac)3·H2O (Ln = Tb, Eu) complexes by C60 fullerene at 293 K was detected and investigated. The dependences of quenching efficiency on C60 concentration obtained from data on the decrease in the photoluminescence intensity and Ln3+* lifetimes obey the Stern-Volmer law. Quenching is due to inductive-resonant energy transfer from Ln3+* to C60 fullerene. The bimolecular rate constants for quenching, the overlap integrals of the Ln3+* photoluminescence spectra with the C60 absorption spectra, and the critical energy transfer distances were determined. No sensitized luminescence of C60 in the system studied was detected. [ABSTRACT FROM AUTHOR]

The reduction of fullerene C60 by Zn and Mg in DMF was studied both in the presence and absence of KOH. Fullerene C60 was reduced in these systems to form the C60 n– ( n = 1, 2, and 3) anions. The anions were detected by optical and ESR spectroscopies. It was found that Mg reduced C60 to the monoanion, Mg/KOH and Zn reduced C60 to the dianion, and Zn/KOH reduced C60 to the trianion. Like KCN, potassium hydroxide adds to fullerene upon interaction with C60 in DMF. The reaction of C60 with KOH in benzonitrile was accompanied by the generation of the fullerene monoanion. A possible mechanism of the formation of fullerene monoanions in the presence of KOH is discussed. The degradation of the C60 n– anions in air was studied. [ABSTRACT FROM AUTHOR]

New fullerenopyrrolidines were synthesized by the three-component reactions of fullerene C60, N-methylglycine, and aromatic aldehydes, viz., N, N-bis(2-chloroethyl)-4-aminobenzaldehyde, N-(2-chloroethyl)- N-methyl-4-aminobenzaldehyde, indole-3-carbaldehyde, 4-phenylbenzaldehyde, and anthracene-9-carbaldehyde. The structures of the resulting compounds were established by spectroscopic methods. [ABSTRACT FROM AUTHOR]

Paramagnetic products of chemical (by diazabicycloene derivatives) and electrochemical reduction of the dicarbethoxy derivative and phosphorylated methane[60]fullerenes were studied by ESR. In all cases, one-electron reduction affords radical anions ( g = 1.9998—1.9999, Δ H = 0.20—0.28 mT), and further reduction produces the secondary radicals ( g = 2.0004—2.0010, Δ H = 0.020—0.028 mT). The rate constants for formation and decay of the radical anions in chemical reduction depend slightly on the nature of the reducing agent and substituents in the methanofullerenes. The retro-Bingel reaction occurs during two-electron reduction. [ABSTRACT FROM AUTHOR]

The products of reaction of fullerene C60 with fuming sulfuric acid were precipitated from a solution with water and triethylamine and studied by IR and ESR spectroscopies. A comparison of the obtained data with the spectra of fullerene, dimers C120 and C120O, and fullerene polymers produced by photopolymerization allowed the conclusion that fullerene polymers were formed by fullerene oxidation with fuming sulfuric acid. [ABSTRACT FROM AUTHOR]

The problem of existence of η4-π-complexes of transition metal atoms with Ñ60 fullerene and its simplest bowl-shaped hydrocarbon precursor, corannulene (Ñ20H10), is discussed in the framework of the HF/3-21G and DFT/TZ2P methods. The molecular structures of corannulene and Ñ60 fullerene derivatives, namely, C20H14, C20H16, C60H4, and C60H6 were simulated. These molecules can form stable η4-π-complexes C20H14Fe(CO)3, C20H16Fe(CO)3, C60H4Fe(CO)3, and C60H6Fe(CO)3 in which the Fe atom interacts with C atoms of a fulvene-like or butadiene-like conjugated fragment of the hydrocarbon ligands. The energies of the η4-π-bonds in the complexes under study were compared with the corresponding bond energies in the classical complexes C4H6Fe(CO)3 and C5H6Fe(CO)3. The geometric parameters of C4H6Fe(CO)3 and C5H6Fe(CO)3 obtained from DFT calculations are close to the experimental values. Stabilities of the η4-π-complexes studied and their η5-π-analogs were compared. [ABSTRACT FROM AUTHOR]

The ability of cyclopentadienyl type derivatives of corannulene C20H10 and fullerene I h -C60 to form η5-π-complexes and the problem of their existence is discussed. MNDO/PM3 calculations of half-sandwich complexes η5-π-MC20H15, η5-π-MC20H, η5-π-MC60H5, η5-π-MC60H5 and sandwich complexes 2η5-π-M(C20H15)2, 2η5-π-M(C20H15)2, 2η5-π-M(C60H5)2 (M=Si, Ge, Sn, Pb) were performed. For all systems studied, local minima were found on corresponding potential energy surfaces and the heats of formation, geometric parameters, and distributions of effective atomic charges were calculated. Sandwich complexes are most likely to exist with M=Si and Ge. The energy and geometric characteristics of η5-π-complexes of corannulene were compared with those of η5-π-complexes of fullerene I h -C60. It was concluded that the results of quantum-chemical calculations of sandwich type corannulene derivatives can be used for simulation of the geometry and electronic structure of analogous complexes of fullerene I h -C60. [ABSTRACT FROM AUTHOR]

The product of the interaction of fullerene C60 with dibenzenechromium (DBC) was studied by ESR and IR spectroscopy. The ESR spectrum contains a signal of the radical cation DBC+. A signal of the C60 − anion is virtually absent, which is most likely related to its broadening. The IR spectrum contains bands characteristic of the DBC+ cation in the (DBC)I molecule and four bands characteristic of C60 −. The data obtained indicate the interaction of C60 molecules with the environment in the crystal structure of the complex. [ABSTRACT FROM AUTHOR]

An efficient catalytic method for cycloaddition of diazo amides to fullerene C 60 in the presence of the three-component catalyst Pd(acac) 2-PPh 3-Et 3Al was developed. The yields and selective formation of the target cycloadducts do not depend on the structure of the starting diazo compound. [ABSTRACT FROM AUTHOR]

An efficient catalytic method for cycloaddition of diazo amides to fullerene C 60 in the presence of the three-component catalyst Pd(acac) 2-PPh 3-Et 3Al was developed. The yields and selective formation of the target cycloadducts do not depend on the structure of the starting diazo compound. [ABSTRACT FROM AUTHOR]

The reactions of fullerene C60 with bromo(dimethoxyphosphoryl)acetates in the presence of NaH in toluene afforded alkoxycarbonyl(dimethoxyphosphoryl)methanofullerenes whose structures were established by UV, IR, and 1H, 13C, and 31P NMR spectroscopy. [ABSTRACT FROM AUTHOR]