Synlett 2022; 33(06): 585-588
DOI: 10.1055/a-1750-8481
letter

Thorpe–Ingold Effect on High-Performance Chiral π–Copper(II) Catalyst

Kazuki Nishimura
,
This work was supported by funds from the NOVARTIS Foundation (Japan) for the Promotion of Science (to K.I.), and from the Nagoya University Graduate Program of Transformative Chem-Bio Research (GTR, to K.N.).


Abstract

The Thorpe–Ingold effect was applied to the design of a chiral ligand of π–copper(II) catalysts for the enantioselective α-fluorination of N-acyl-3,5-dimethylpyrazoles, and also for the enantioselective Mukaiyama–Michael, Diels–Alder, and 1,3-dipolar cycloaddition reactions of N-acryloyl-3,5-dimethylpyrazoles. The use of β,β-dimethyl-β-arylalanine-type ligand gave desired products with higher enantioselectivity compared to with previously reported β-arylalanine-type ligands.

Supporting Information



Publication History

Received: 18 December 2021

Accepted after revision: 25 January 2022

Publication Date:
26 January 2022 (online)

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Georg Thieme Verlag KG
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