A bimetallic catalyst and dual role catalyst: synthesis of N-(alkoxycarbonyl) indoles from 2-(alkynyl) phenylisocyanates

S Kamijo, Y Yamamoto

Index: Kamijo, Shin; Yamamoto, Yoshinori Journal of Organic Chemistry, 2003 , vol. 68, # 12 p. 4764 - 4771

Full Text: HTML

Citation Number: 119

Abstract

3-Allyl-N-(alkoxycarbonyl) indoles are synthesized via the reaction of 2-(alkynyl) phenylisocyanates and allyl carbonates in the presence of Pd (PPh3) 4 (1 mol%) and CuCl (4 mol%) bimetallic catalyst. It is most probable that Pd0 acts as a catalyst for the formation of a π-allylpalladium alkoxide intermediate and CuI behaves as a Lewis acid to activate the isocyanate, and the cyclization step proceeds with a cooperative catalytic activity of Pd ...