Synthesis of Metal Fullerene Complexes by the Use of Fullerene Halides

Abstract

K(C 60 R 5 ) ( 1, R = Me, Ph) was generated by deprotonation of C 60 R 5 H ( 2 ) and allowed to react with N -fluoropyridinium triflate and N -chloro- and N -bromosuccinimide in benzene at 25 °C for 10 min to obtain halogenated fullerenes C 60 R 5 X ( 3a: R = Me, X = F; 3b: R = Me, X = Cl; 3c: R = Me, X = Br; 4a: R = Ph, X = F; 4b: R = Ph, X = Cl, 4c: R = Ph, X = Br) in good yield. The pentamethyl[60]fullerene halides are useful for the synthesis of a variety of η 5 -fullerene metal complexes. The reaction of the fullerene bromide 3c with the low-valent transition metal complexes Na[Re(CO) 4 ], Fe(CO) 5, Ru 3 (CO) 12, and Na[Co(CO) 4 ] gave Re(η 5 -C 60 Me 5 )(CO) 3 ( 5 ), Fe(η 5 -C 60 Me 5 )Br(CO) 2 ( 6 ), Ru(η 5 -C 60 Me 5 )Br(CO) 2 ( 7 ), and Co(η 5 -C 60 Me 5 )(CO) 2 ( 8 ), respectively. The structures of halide 3c and rhenium complex 5 were determined by X-ray crystallography. Electrochemical measurements on 3b and 3c were also performed. The iron complex 6 was converted into Fe(η 5 -C 60 Me 5 )Cp ( 9 ), Fe(η 5 -C 60 Me 5 )Me(CO) 2 ( 10 ), Fe(η 5 -C 60 Me 5 )(CO) 2 (CCH) ( 11 ), and Fe(η 5 -C 60 Me 5 )(CO) 2 (CCPh) ( 12 ), by ligand exchange reactions.