Dimethyl Carbonate as a Methylating Agent. The Selective Mono-C-methylation of Alkyl Aryl Sulfones

Abstract

At 180–210 °C, α-methylene sulfones (both benzyl aryl and alkyl aryl sulfones, RCH₂SO₂AR: R = Ph, p-ClC₆H₄, Ar = Ph, p-ClC₆H₄, p-MeC₆H₄, and R = Me, Ar = Ph, p-ClC₆H₄, p-MeC₆H₄) react with dimethyl carbonate to yield the corresponding mono-C-methyl derivatives [RCH(CH₃)SO₂Ar] in a selectivity >99%, at conversions of 76–99% (isolated yields: 97–92%).

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