Electron-transfer-induced substitution of alkylated C60 chlorides with proton sponge.
A series of alkylated C(60) chlorides 1,4-RC(60)Cl (1) were found to undergo nucleophilic substitution with 1,8-bis(dimethylamino)naphthalene (2), affording 1,4-RC(60)Ar [3, Ar = 4,5-bis(dimethylamino)-1-naphthyl] in good yields. An S(RN)1 mechanism, initiated by a single-electron transfer from 2 to 1, is proposed on the basis of the enhanced rates compared with the rate of the S(N)1 reaction of 1 with anisole. The involvement of free radicals in the reaction is supported by the formation of a small amount of dimer RC(60)-C(60)R (4) as a byproduct. The enhanced ability of C(60) chlorides 1 to accept an electron, attributable to the inductive effect of the directly attached chlorine atom, was demonstrated by its reduction potential and calculated LUMO energy.
Lee
Yangsoo
Y
Institute for Chemical Research, Kyoto University, and CREST, Japan Science and Technology Corporation, Uji, Kyoto 611-0011, Japan.
Kitagawa
Toshikazu
T
Komatsu
Koichi
K