Aminomethylation of enals through carbene and acid cooperative catalysis: concise access to β(2)-amino acids.
نویسندگان
چکیده
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.
منابع مشابه
Oxidative γ-addition of enals to trifluoromethyl ketones: enantioselectivity control via Lewis acid/N-heterocyclic carbene cooperative catalysis.
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ورودعنوان ژورنال:
- Angewandte Chemie
دوره 54 17 شماره
صفحات -
تاریخ انتشار 2015