N-amination and subsequent oxidation of imidazo[1,2-a]pyrimidines
Abstract
Imidazo[1,2-a]pyrimidines are N-aminated at N-1 by O-p-tolylsulphonylhydroxylamine. Subsequent oxidation of the resulting N-amino-salts with bromine generally results in the corresponding 1,1′-azoimidazo[1,2-a] pyrimidinium salts.