无溶剂微波照射下2-取代苯并咪唑的合成

Solvent-Free Synthesis of 2-Substituted Benzimidazoles under Microwave-Irradiation Using PPA as a Catalyst

用PPA作催化剂 ,在无溶剂微波照射下合成了 10种 2 取代苯并咪唑 ,为该类化合物的合成提供了一种新方法 .与常规方法相比 ,反应时间大大缩短 ,产率与传统合成方法相当 .

A novel microwave-enhanced synthesis of 2-substituted benzimidazoles, 2-benzimidazol-2-one and thione by the reaction o-phenylenediamine with organic acids, urea and thiourea, respectively, using polyphosphoric acid (PPA) as a catalyst under solvent-free conditions has been developed. This method provides a simple and inexpensive access to the title compounds.