Photoredox-catalyzed hydrogenation of alkenes assisted by an in situ generated PPh3(OH) radical and acetic acid

Abstract

Herein, a practical, mild and convenient strategy was disclosed for the hydrogenation of alkenes under photocatalytic conditions through a HAT/protonation process. A combination of experimental and computational studies suggested that water was activated by a phosphine radical cation to generate the critical intermediate, the PR₃(OH) radical, which acted as a “free” hydrogen atom to facilitate the initial HAT process.