Carbene-Catalyzed Activation of Remote Nitrogen Atoms of (benz)imidazole-derived aldimines for Enantioselective Synthesis of Heterocycles.

Carbene-Catalyzed Activation of Remote Nitrogen Atoms of (benz)imidazole-derived aldimines for Enantioselective Synthesis of Heterocycles.
Angew Chem Int Ed Engl. 2021 Jan 19;:
Authors: Yang X, Xie Y, Xu J, Ren S, Mondal B, Zhou L, Tian W, Zhang X, Hao L, Jin Z, Chi YR
Abstract
A new mode of carbene-catalyzed heteroatom activation and asymmetric reactions is disclosed. The reaction starts with addition of a carbene catalyst to a (benz)imidazole-derived aldimine substrate. Subsequent oxidation and proton transfer lead to the formation of a catalyst-bound triaza-diene as the key intermediate, in which the nitrogen atom at a site remote to the catalyst-substrate bond is activated. This unusual triaza-diene intermediate then undergoes highly enantioselective reactions with activated ketones through a concerted asynchronous pathway, as supported by mechanistic studies and preliminary density function theory calculation.
PMID: 33469976 [PubMed - as supplied by publisher]

Source: Angewandte Chemie - January 19, 2021 Category: Chemistry Authors: Yang X, Xie Y, Xu J, Ren S, Mondal B, Zhou L, Tian W, Zhang X, Hao L, Jin Z, Chi YR Tags: Angew Chem Int Ed Engl Source Type: research