一个简单、环境友好的硅胶固载硫酸催化Biginelli反应体系(英文)

A protocol for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and-thiones was developed by means of a three-component condensation of an aldehyde,a β-dicarbonyl compound,and urea or thiourea in acetic acid catalyzed by silica-bonded S-sulfonic acid.Compared to the classical Biginelli reaction conditions,this new protocol has the advantages of consistently excellent yields and short reaction times.After the reaction,the catalyst could be recovered easily and reused with little change in its activity.

苯甲酸催化一锅合成3,4-二氢嘧啶-2(1H)-酮

介绍了用苯甲酸作催化剂利用Biginelli反应在无溶剂条件下，一锅合成标题化合物的方法。和传统的Biginelli反应条件比较，此法有反应时间短（3～5h）和收率高（70％～97％）的特点。

6-甲基-4-对羟苯基-5-乙酰基-3,4-二氢嘧啶-2-酮的合成

以氨基磺酸为催化剂,对羟基苯甲醛、乙酰丙酮、尿素为原料,在无水乙醇中进行环化缩合反应(Biginelli反应),合成6-甲基-4-对羟苯基-5-乙酰基-3,4-二氢嘧啶-2-酮,并对产品进行表征.结果表明,氨基磺酸具有较好的催化效果,适宜的合成条件为:n(对羟基苯甲醛)∶n(乙酰丙酮)∶n(尿素)=1.0∶2.0∶5.0,氨基磺酸为2.0 g,反应时间为2.0 h,收率可达52.8%.