A diselenide additive enables photocatalytic hydroalkoxylation of gem-difluoroalkenes

Abstract

A photocatalytic hydroalkoxylation reaction enables the coupling of aliphatic alcohols with gem-difluoroalkenes, expanding the scope of accessible α,α-difluorinated ethers, a desirable substructure for medicinal and agricultural chemists. This reaction exploits an uncommon diselenide co-catalyst to facilitate the net hydrofunctionalization process, which contrasts alternate single-electron reactions that deliver dioxidation products. Future use of this co-catalyst might enable other currently unknown photocatalytic reactions.

Scheme 1.

Accessing α,α-difluorinated ethers from gem-difluoroalkenes.

Scheme 2.

Scope of hydroalkoxylation reaction. ^a 6a–j (0.50 mmol), 9 (0.75 mmol), PC-1: 9-mesityl-3,6-di-tert-butyl-10-phenylacridinium tetrafluoroborate (6.0 μmol), and 1,2-dibenzyldiselane (0.025 mmol) in PhMe (2.0 mL) irradiated with a 40 W 427 nm LED under an atmosphere of argon or N₂. Isolated yields represent an average of two independent reactions. Ar = −C₆H₂(3,4,5-OMe).

Scheme 3.

Proposed reaction mechanism.