C-H Fluoromethoxylation of Arenes by Photoredox Catalysis

Angew Chem Int Ed Engl. 2023 Jan 26;62(5):e202215920. doi: 10.1002/anie.202215920. Epub 2022 Dec 27.

Abstract

Redox-active N-(fluoromethoxy)benzotriazoles were made accessible from fluoroacetic acid and hydroxybenzotriazoles via electrodecarboxylative coupling. After alkylation, they become effective monofluoromethoxylation reagents, enabling the photocatalytic C-H functionalization of arenes. Thus, irradiation of 1-(OCH2 F)-3-Me-6-(CF3 )benzotriazolium triflate with blue LED light in the presence of [Ru(bpy)3 (PF6 )2 ] promotes the synthesis of diversely functionalized aryl monofluoromethyl ethers. This method allows the late-stage functionalization of biologically relevant structures without relying on ecologically problematic halofluorocarbons.

Keywords: Electrosynthesis; Fluorine; Monofluoromethyl; Photochemistry; Radical Reactions.