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(η 5 -C 60 Me 5 )Cl(CO) 2 ( 1 ), was prepared by the reaction of [RuCl 2 (CO) 3 ] 2 with C 60 Me 5 K 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(η 5 -C 60 Me 5 )Cl(PEt 3 )(CO) ( 2 ) and Ru(η 5 -C 60 Me 5 )Cl(PPh 3 )(CO) ( 3 ). Isocyanide complexes, Ru(η 5 -C 60 Me 5 )Cl( t BuNC)(CO) ( 4 ), Ru(η 5 -C 60 Me 5 )Cl(MeNC)(CO) ( 5 ), and Ru(η 5 -C 60 Me 5 )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(η 5 -C 60 Me 5 )Cl( t BuNC) 2 ( 7 ) and Ru(η 5 -C 60 Me 5 )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(η 5 -C 60 Me 5 )Me(CO) 2 ( 9 ), and a (trimethylsilyl)methyl complex, Ru(η 5 -C 60 Me 5 )(CH 2 SiMe 3 )(CO) 2 ( 10 ), respectively. Alkynylation reactions gave various alkynyl complexes, Ru(η 5 -C 60 Me 5 )(C⋮CPh)(CO) 2 ( 12 ), Ru(η 5 -C 60 Me 5 )(C⋮C n Bu)(CO) 2 ( 13 ), Ru(η 5 -C 60 Me 5 )(C⋮CSiMe 3 )(CO) 2 ( 14 ), and Ru(η 5 -C 60 Me 5 )(C⋮CH)(CO) 2 ( 15 ). X-ray single-crystal structure analyses and electrochemical studies of a series of new ruthenium fullerene complexes were performed.