Cyclopentadiene-based Brønsted acid as a new generation of organocatalyst for transfer hydrogenation of 2-substituted quinoline derivatives

Abstract

Abstract A simple and readily available cyclopentadiene-based Bronsted acid was employed to catalyze the transfer hydrogenation of 2-substituted quinolines using Hantzsch ester as the hydrogen source. This conceptually new designed organocatalyst demonstrates remarkably high efficiency for this transformation and a variety of substituted 1,2,3,4-tetrahydroquinoline derivatives were afforded in excellent yields under mild reaction conditions.