Exohedral mono- and bimetallic hydride complexes of rhodium and iridium with C60 and C70: syntheses and electrochemical properties

Syntheses of mono- and bimetallic hydride complexes of rhodium and iridium with fullerenes C60 and C70 are described and the results of their cyclic voltammetry (CV) studies are presented. The metal-containing [HM(CO)(PPh3)2] moiety (M=Rh and Ir) coordinates with high stereo- and regioselectivity to the 1,2 bond of these fullerenes to form the only isomer in both cases. The attachment of the second [HM(CO)(PPh3)2] moiety results in a complex mixture of positional and geometric isomers. Due to a high rate of formation, metallofullerene complexes may be generated in situ in the electrochemical cell. The electrochemical behavior (their redox potentials and stability of the oxidized and reduced forms) of the studied C60 and C70 organometallic derivatives with the same metal-containing fragment is identical.