Ruthenium(II) complexes of pentamethylated [60]fullerene. Alkyl, alkynyl, chloro, isocyanide, and phosphine complexes

A ruthenium chloro dicarbonyl complex bearing a pentamethylated [60]fullerene ligand, Ru(eta(5)-C60Me5)Cl(CO)(2) (1), was prepared by the reaction of [RuCl2(CO)(3)](2) with C60Me5K in THF. A variety of ligand exchange reactions involving the carbonyl and chloro ligands took place on the ruthenium metal attached directly to the exterior of the fullerene framework. Treatment of 1 with a phosphine ligand afforded phosphine complexes, Ru(eta(5)-C60Me5)Cl(PEt3)(CO) (2) and Ru(eta(5)-C60Me5)Cl(PPh3)(CO) (3). Isocyanide complexes, Ru(eta(5)-C60Me5)Cl((BuNC)-Bu-t)(CO) (4), Ru(eta(5)-C60Me5)Cl(MeNC)(CO) (5), and Ru(eta(5)-C60Me5)Cl(XylNC)(CO) (6; Xyl = 2,6-dimethylphenyl), were also prepared by reaction with an appropriate isocyanide ligand, while the use of a large excess of the same isocyanides gave bis(isocyanide)complexes, Ru(eta(5)-C60Me5)Cl((BuNC)-Bu-t)(2) (7) and Ru(eta(5)-C60Me5)Cl(XylNC)(2) (8). Metathetic replacement of the halogen atom on the transition-metal fullerene complexes was achieved: methyl and (trimethylsilyl)methyl Grignard reagents reacted with 1 to give a methyl complex, Ru(eta(5)-C60Me5)Me(CO)(2) (9), and a (trimethylsilyl)methyl complex, Ru(eta(5)-C60Me5)(CH2SiMe3)(CO)(2) (10), respectively. Alkynylation reactions gave various alkynyl complexes, Ru(eta(5)-C60Me5)(Cequivalent toCPh)(CO)(2) (12), Ru(eta(5)-C60Me5)(Cequivalent toC(n)Bu)(CO)(2) (13), Ru(eta(5)-C60Me5)(Cequivalent toCSiMe(3))(CO)(2) (14), and Ru(eta(5)-C60Me5)(Cequivalent toCH)(CO)(2) (15). X-ray single-crystal structure analyses and electrochemical studies of a series of new ruthenium fullerene complexes were performed.