Syntheses of Spiro[cyclopent[3]ene-1,3′-indole]s and Tetrahydrocyclohepta[<i>b</i>]indoles from 2,3-Disubstituted Indoles through Sigmatropic Rearrangement
作者:Amrita Chakraborty、Koushik Goswami、Akhila Adiyala、Surajit Sinha
DOI:10.1002/ejoc.201300888
日期:2013.11
for the syntheses of a series of 2′-arylspiro[cyclopent[3]ene-1,3′-indole]s and 6-alkyl-5,6,7,10-tetrahydrocyclohepta[b]indoles in good yields by cyclization through a sigmatropic rearrangement of suitable 2,3-disubstituted indoles. These precursors that contain a 4-chloro-2-butenyl side chain at the 3-position were obtained as a mixture of (E) and (Z) isomers through the reactions of o-alkynylanilines
为合成一系列 2'-芳基螺[环戊 [3] 烯-1,3'-吲哚] 和 6-烷基-5,6,7,10-四氢环庚 [b] 开发了一种 NaOH 介导的方案通过合适的 2,3-二取代吲哚的 sigmatropic 重排环化,以良好的产率获得吲哚。通过邻炔基苯胺和 3,4-二氯-1-丁烯的反应,以 (E) 和 (Z) 异构体的混合物形式获得这些在 3-位含有 4-氯-2-丁烯基侧链的前体. 环化策略是通用的,通过改变 3-(4-chlorobut-2-enyl)-1H-indole-1-carboxylate 2-位上的取代基来实现这两种重要的药用支架。该反应可能通过吲哚中间体的乙烯基环丙烷取代基的 [1,3]- 和 [3,3]- σ 重排进行。