Tandem beta-enamino ester formation and cyclization with o-alkynyl anilines catalyzed by InBr3: efficient synthesis of beta-(N-indolyl)-alpha,beta-unsaturated esters.

Research paper by Kenichi K Murai, Shoko S Hayashi, Nobuhiro N Takaichi, Yasuyuki Y Kita, Hiromichi H Fujioka

Indexed on: 31 Dec '08Published on: 31 Dec '08Published in: Journal of Organic Chemistry


A tandem reaction providing beta-(N-indolyl)-alpha,beta-unsaturated esters from beta-keto esters and o-alkynyl anilines was developed. Z-Alkenes were selectively formed due to the stability of the beta-enamino ester as an intermediate of the reaction. This reaction includes the intermolecular beta-enamino ester formation and intramolecular cyclization catalyzed by InBr(3).