Benzimidazolylidene-Stabilized Borenium Ion for Catalytic Hydrogenation of N-Heterocycles.

Abstract

Herein, we report the synthesis of a benzimidazolylidene-stabilized borane adduct and its borenium ion. This borenium ion was used as a metal-free catalyst for hydrogenating various substituted quinoline N-heterocycles under ambient conditions. Furthermore, this method was utilized to synthesize two drug molecules: galipinine and angustureine. A detailed DFT study was performed to understand this metal-free catalytic hydrogenation.