三组分串联反应一锅合成多环稠合的1,5-苯并二氮杂?化合物

以取代的邻苯二胺、1,3-环戊二酮或1,3-环己二酮(5,5-二甲基-1,3-环己二酮)、2,3-二羰基化合物为原料,无水乙醇为溶剂,对甲苯磺酸为催化剂,经2~5 h串联反应一锅合成43种新颖的1,5-苯并二氮杂?化合物,产率最高可达95%.该反应序列首先通过两次的亲核加成-脱水反应过程,形成分子内亚胺和烯胺结构的活性中间体,然后再经分子内的碳碳偶联环合-质子转移等过程,生成多环稠合的1,5-苯并二氮杂?目标化合物,实现了在一个反应体系中形成一个二氮杂七元环和四个新化学键(两个C—N,一个C=C,一个C—C).该方法操作简单,反应便捷,对环境友好,产率高,为1,5-苯并二氮杂?化合物的合成提供绿色环保,高效简便的合成思路.

One-Pot Synthesis of 1,5-Benzodiazepine Compounds by Three-Component Tadem Reaction

43 novel 1,5-benzodiazepine compounds were obtained via one-pot multicomponent and tadem reactions for 2~5 h and the yield of the target compounds is up to 95%.These reactions were achieved by reacting substituted 1,2-phenylenediamines,1,3-cyclopentanedione or 1,3-cyclohexanedione(5,5-dimethyl-1,3-cyclohexanedione),2,3-dicarbonyl compounds with p-toluenesulfonic acid as catalyst in EtOH.The active intermediates with the imine and enamine structures in the molecule were formed by two nucleophilic addition-dehydration processes and then 1,5-benzodiazepine compounds were obtained via carbon-carbon coupling cyclization and proton transfer processes,which realized the construction of one new sevenmembered ring and four new chemical bonds(two C—N,one C=C,one C—C)in one-pot.It provides a green,environmentally friendly,efficient and simple synthetic thought for the synthesis of 1,5-benzodiazepine compounds.