Addition of NN-dimethylaniline oxides to nitrilium salts and to dimethyl acetylenedicarboxylate. Direct alkylamination of NN-dimethylanilines

Abstract

NN-Dimethylaniline oxide (1) and its ring-substituted derivatives react with N-alkylacetonitrilium salts to give the corresponding 2- and 4-(N-alkylacetamido) dimethylanilines. The mechanism, which involves migration of an amide group from the aniline nitrogen onto the ring, is discussed. Addition of the oxide (1) to dimethyl acetylenedicarboxylate leads either to demethylation of the aniline (main path in dichloromethane) or to a rearrangement, which involves migration of the succinyl moiety onto the ortho-carbon (in ethanol).