Regioselective Synthesis of 1,4-Di(organo)[60]fullerenes through DMF-assisted Monoaddition of Silylmethyl Grignard Reagents and Subsequent Alkylation Reaction

Monoaddition of Grignard reagents, in particular tri(organo)silylmethyl magnesium chlorides, to [60]fullerene took place smoothly in the presence of dimethylformamideto produce (organo)(hydro)[60]fullerenes, (C60RH)-H-1, in good yield (up to 93% isolated yield). The hydrofullerene was then deprotonated to generate the corresponding anion, C60R-, which was then alkylated to obtain 58 pi-electron di(organo)[60]fullerenes, (C60RR2)-R-1, in good to high yield (up to 93% overall yield). The two-step methodology provides a wide variety of 1,4-di(organo)[60] fullerenes bearing the same or different organic addends on the [60] fullerene core. By changing the addends, one can control the chemical and physical properties of the compounds at the molecular and bulk levels.