A simple aza wittig-mediated pyrimidine annulation reaction
作者:Edward C. Taylor、Mona Patel
DOI:10.1002/jhet.5570280810
日期:1991.12
Treatment of heterocyclic o-aminonitriles and o-aminoesters 1a-5a with dibromotriphenylphosphorane gives iminophosphoranes 1b-5b which undergo a facile aza-Wittig reaction at room temperature with phenyl isocyanate to provide the carbodiimides 1c-5c. Treatment of the latter intermediates with ammonia leads to intramolecular ring closure of the initially formed guanidines to provide the fused 4-aminopyrimidines