Rhodium(I)-Catalyzed Synthesis of Indoles: Amino-Claisen Rearrangement of <i>N</i>-Propargylanilines
作者:Akio Saito、Shoko Oda、Haruhiko Fukaya、Yuji Hanzawa
DOI:10.1021/jo8022523
日期:2009.2.20
Mild and facile preparations of 2-substituted or 2,3-disubstituted indole compounds were achieved by RhH(CO)(Ph3P)3 (4−10 mol %)-catalyzed reaction of N-propargylanilines in hexafluoroisopropyl alcohol (HFIP). The formation of indoles was proven to be derived from an o-allenylaniline intermediate, which was generated by the Rh(I)-catalyzed amino-Claisen rearrangement of N-propargylanilines. The catalytic
通过RhH(CO)(Ph 3 P)3(4-10 mol%)催化的N-炔丙基苯胺在六氟异丙醇(HFIP)中的反应,可以实现轻度和简便地制备2-取代或2,3-二取代的吲哚化合物。吲哚的形成被证明源自邻-烯丙基苯胺中间体,其是由R-(I)催化的N-炔丙基苯胺的氨基-克莱森重排产生的。该催化体系也可用于通过在HFIP中在K 2 CO 3(3当量)存在下使N-烷基苯胺(1当量)与炔丙基溴(1.3当量)反应来进行吲哚的一锅合成。活性催化剂被证明是[Rh(CO)(Ph由RhH(CO)(Ph 3 P)3和HFIP原位生成3 P)2 ] OCH(CF 3)2。通过单晶X射线晶体学分析确认了[Rh(CO)(Ph 3 P)2 ] OCH(CF 3)2的结构。