Monomethylation of Aromatic Rings by Friedel-Crafts Reaction with Chloromethyl Sulfide

Abstract

A novel method for the introduction of a methyl group into aromatic rings in described. Friedel-Crafts reactions of ethyl α-(chloromethylthio)acetate (3k) and α-chloromethylthio-γ-butyrolactone (3m) with an arene in the presence of stannic chloride gave ethyl α-(arylmethylthio)-acetate (6) and α-arylmethylthio-γ-butyrolactone (7), respectively, which were easily converted to the corresponding methylated arene (8) by reductive desulfurization with Raney nickel or zinc dust-acetic acid.