Cu(II) acetate- and Mn(III) acetate-mediated radical reactions of [60]fullerene with ketonic compounds.

The copper(II) acetate monohydrate- or manganese(III) acetate dihydrate-mediated reaction of [60]fullerene with beta-keto esters 1a-1c or with beta-diketones 1d,1e in the presence of 4-dimethylaminopyridine afforded only dihydrofuran-fused C60 derivatives 2a-2e. However, aromatic methyl ketones 3a-3c gave two kinds of products: methanofullerenes 4a-4c and dihydrofuran-fused C60 derivatives 5a,5b. Possible reaction mechanisms are proposed.