Organic photoredox-catalyzed unimolecular PCET of benzylic alcohols

Chem Sci. 2025 Jan 8. doi: 10.1039/d4sc07048h. Online ahead of print.

Abstract

Proton-coupled electron transfer (PCET) is a crucial chemical process involving the simultaneous or sequential transfer of protons and electrons, playing a vital role in biological processes and energy conversion technologies. This study investigates the use of an organic photoredox catalyst to facilitate a unimolecular PCET process for the generation of alkyl radicals from benzylic alcohols, with a particular focus on alcohols containing electron-rich arene units. By employing a benzophenone derivative as the catalyst, the reaction proceeds efficiently under photoirradiation, achieving significant yields without the need for a Brønsted base. The findings highlight the potential of this unimolecular PCET mechanism to streamline radical generation in organic synthesis, offering a more efficient and flexible alternative to conventional methods.