Accessing Aryldifluoromethyl Derivatives through Alkene Insertion into Benzylic C–F Bonds

Abstract

We report our formal insertion of alkenes into benzylic C–F bonds of electron-deficient perfluoroalkylarenes under organophotocatalytic conditions with Et₃N·3HF as an external fluoride source. The absence of a fluoride scavenger or other external reductant permits the formation of a carbocation and its trapping by other nucleophiles. This three-component reaction represents one of the most efficient methods for preparing a variety of complex partially fluorinated organic molecules. This redox-neutral transformation features mild conditions, a broad substrate scope, and extraordinary functional-group tolerance. Moreover, several examples of modifications of complex drug molecules further demonstrated its utility.

Key words

photocatalysis - organocatalysis - aryldifluoromethyl compounds - late-stage functionalization - C–F bond cleavage - radical–polar crossover reaction

Publication History

Received: 13 March 2023

Accepted after revision: 04 April 2023

Accepted Manuscript online:
04 April 2023

Article published online:
09 May 2023

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