NHC-catalyzed Enantioselective Synthesis of β-trifluoromethyl-β-hydroxyamides

Overview

Journal Beilstein J Org Chem

Specialty Chemistry

Date 2020 Jul 25

PMID 32704323

Citations 3

Authors

Alyn T Davies

Mark D Greenhalgh

Alexandra M Z Slawin

Andrew D Smith

Affiliations

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Abstract

The N-heterocyclic carbene (NHC)-catalyzed formal [2 + 2] cycloaddition between α-aroyloxyaldehydes and trifluoroacetophenones, followed by ring opening with an amine or a reducing agent is described. The resulting β-trifluoromethyl-β-hydroxyamide and alcohol products are produced with reasonable diastereocontrol (typically ≈70:30 dr) and excellent enantioselectivity, and they can be isolated in moderate to good yield as a single diastereoisomer.

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