Michael reaction of indoles with 3-(2′-nitrovinyl)indole under solvent-free conditions and in solution. An efficient synthesis of 2,2-bis(indolyl)nitroethanes and studies on their reduction
作者:Manas Chakrabarty、Ramkrishna Basak、Nandita Ghosh、Yoshihiro Harigaya
DOI:10.1016/j.tet.2003.12.021
日期:2004.2
Michael reaction of 3-(2′-nitrovinyl)indole with eight 3-unsubstituted indoles on TLC-grade silica gel furnished unsymmetrical bis(indolyl)nitroethanes in 7–12 min under microwave irradiation and in 8–14 h at rt. In contrast, the p-TsOH-catalysed reaction of the nitrovinylindole with the 3-unsubstituted and two 3-substituted indoles in solution under reflux furnished both unsymmetrical and symmetrical
在TLC级硅胶上,3-(2'-硝基乙烯基)吲哚与八个3-未取代的吲哚的迈克尔反应在微波辐射下7-12分钟和室温下在8-14小时内提供了不对称的双(吲哚基)硝基乙烷。相反,在回流条件下,溶液中硝基乙烯基吲哚与3-未取代和两个3-取代的吲哚的p -TsOH催化反应提供了不对称和对称的双(吲哚基)硝基乙烷,后者是由新的串联迈克尔加成反应消除的。迈克尔加成反应。2',3''-双(吲哚基)硝基乙烷的合成,两种生物活性海洋代谢产物的前体核心结构以及将2,2-双(3'-吲哚基)硝基乙烷还原为相应的乙胺的过程ñ-乙酰基衍生物,已经实现。重要的是,尝试用缓冲的TiCl 3水解衍生自相应的双(吲哚基)硝基乙烷的三种硝酸盐,这是肟的第一个分离产物(顺/反混合物),这是唯一的产物。