Organocatalytic domino Knöevenagel–Michael reaction in water for the regioselective synthesis of benzo[4,5]imidazo[1,2-a]pyrimidines and pyrido[2,3-d]pyrimidin-2-amines
An organocatalyzed simple and general route towards the regioselectivesynthesis of benzo[4,5]imidazo[1,2-a]pyrimidines and pyrido[2,3-d]pyrimidin-2-amines is developed via L-proline catalyzed domino reaction of 2-aminobenzimidazole or 2,6-diaminopyrimidin-4-one with aldehydes and β-ketoesters in water. High yields within a shorter reaction time, simple purification, and environmentally benign mild
通过L-脯氨酸催化的邻氨基苯甲酸酯反应,建立了有机催化的通用途径进行区域选择性合成苯并[4,5]咪唑并[1,2- a ]嘧啶和吡啶并[2,3- d ]嘧啶2-胺的区域选择性合成。 2-氨基苯并咪唑或2,6-二氨基嘧啶-4-酮与醛和β-酮酸酯的水溶液。在较短的反应时间内实现高收率,简单的纯化以及对环境无害的温和反应条件是使该协议显着适用的关键特征。