The reaction of isatoic anhydride with dimethylsulfoxide. Isolation of products formed through a putative Pummerer rearrangement

Abstract

Reaction of isatoic anhydride with dimethyl sulfoxide at 150oC results in the formation of S-methyl-2-aminobenzothioate as the result of a Pummerer rearrangement. While the reaction can be conducted in the absence of a base, yields of isolated product are higher in the presence of a base. The reaction appears to be optimal using dimethyl sulfoxide as the substrate.