Aminomethylation of Enals through Carbene and Acid Cooperative Catalysis: Concise Access to β<sup>2</sup>‐Amino Acids
Angewandte Chemie International EditionPublished 3 March 2015
Jianfeng Xu, Xingkuan Chen, Ming Wang, Pengcheng Zheng, Bao‐An Song, Yonggui Robin
Citations117
SJR quartileQ1
SJR score5.55
SNIP2.47
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TL;DR
A convergent, organocatalytic asymmetric aminomethylation of α,β-unsaturated aldehydes by N-heterocyclic carbene (NHC) and (in situ generated) Brønsted acid cooperative catalysis is disclosed.
Abstract
A convergent, organocatalytic asymmetric aminomethylation of α,β-unsaturated aldehydes by N-heterocyclic carbene (NHC) and (in situ generated) Brønsted acid cooperative catalysis is disclosed. The catalytically generated conjugated acid from the base plays dual roles in promoting the formation of azolium enolate intermediate, formaldehyde-derived iminium ion (as an electrophilic reactant), and methanol (as a nucleophilic reactant). This redox-neutral strategy is suitable for the scalable synthesis of enantiomerically enriched β(2) -amino acids bearing various substituents.
Keywords
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