Silyl-enolization-asymmetric Claisen rearrangement of 2-allyloxyindolin-3-one:: enantioselective total synthesis of 3a-hydroxypyrrolo[2,3-b]indoline alkaloid alline

Asymmetric Claisen rearrangement triggered by silyl-enolization of 2-(1'-nonel-3'-yloxy)indolin-3-ones was performed in order to prepare 3-(2'-nonenyl)-3-hydroxyindolin-2-ones. Total synthesis of 3-hydroxypyrrolo[2,3-b]indoline alkaloid, (+)-alline was achieved by transformation of the allylic moiety of 3-(2'-nonenyl)-3-hydroxyindolin-2-one to amine followed by reductive cyclization. (c) 2006 Elsevier Ltd. All rights reserved.