Selective synthesis of pyrrolo[1,2-a]azepines or 4,6-dicarbonyl indoles via tandem reactions of alkynones with pyrrole derivatives
作者:Yulei Zhao、Yang Yuan、Murong Xu、Zhong Zheng、Runhua Zhang、Yanzhong Li
DOI:10.1039/c7ob01516j
日期:——
Novel methodologies for the selective synthesis of pyrrolo[1,2-a]azepines or 4,6-dicarbonyl indoles starting from pyrrole derivatives and alkynones are described. When reactions were carried out with 1,2,4-trisubstituted N-propargyl pyrroles using a ZnI2 catalyst, pyrrolo[1,2-a]azepines were obtained. Whereas 4,6-dicarbonyl indoles were produced selectively with 1,2-disubstituted pyrroles in the presence
描述了从吡咯衍生物和炔酮开始选择性合成吡咯并[1,2- a ]氮杂或4,6-二羰基吲哚的新方法。使用ZnI 2催化剂与1,2,4-三取代的N-炔丙基吡咯进行反应时,吡咯并[1,2- a获得了[氮杂环庚烷]。而在硅胶存在下,用1,2-二取代的吡咯选择性地生产4,6-二羰基吲哚。反应结果取决于底物的取代基样式和所选催化剂的性质。对照反应表明,共轭烯胺中间体的形成对于这两个过程都是至关重要的。使用容易获得的起始原料,廉价的催化剂和易于操作的方法,该反应有可能成为合成吡咯并[1,2- a ]氮杂或吲哚的通用方法。