Unlocking Difluorocarbene as a Versatile Precursor to Fluorocarbon Anions and Radicals via Palladium Catalysis

Abstract

Difluorocarbene, a versatile bipolar intermediate, has been widely exploited in ionic-type coupling reactions. Its direct transformation into a fluorinated carbon-radical species, however, has remained a formidable challenge because of the large singlet–triplet energy gap. Here we report an unprecedented strategy that unlocks difluorocarbene as a precursor for both fluorinated carbanions and carbon radicals through the thermolytic homolysis of an aryldifluoromethylpalladium intermediate. This palladium-catalyzed sequential process enables a modular three-component coupling of aryl iodides, alkenes, and ClCF₂H, delivering a broad spectrum of difluoroalkylated arenes in high efficiency. The method features inexpensive and readily available reagents, excellent functional-group tolerance, and opens a new avenue for the precise installation of the difluoromethylene motif.

Keywords

Difluorocarbene - Fluoroalkyl radical - Metal difluorocarbene - Palladium catalysis - Palladium difluorocarbene - Aryldifluoromethylpalladium - Alkenes - Coupling reaction

Publication History

Received: 15 December 2025

Accepted after revision: 02 February 2026

Accepted Manuscript online:
05 February 2026

Article published online:
13 February 2026

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