Dual PCET-Enabled Chemoselective Decarboxylative Sulfinylation with N-Sulfinyl Phthalimides as Bench-Stable Sulfinyl Radical Precursors

Abstract

Herein, we disclose N-sulfinyl phthalimides as a new class of bench-stable and readily accessible sulfinyl radical precursors for the direct decarboxylative sulfinylation of carboxylic acids to sulfoxides via a dual proton-coupled electron transfer (PCET) process. This method demonstrated a remarkable substrate scope and excellent chemoselectivity across a diverse array of sulfoxide compounds under mild conditions. The synthetic utility and practicability of this robust protocol were further highlighted through gram-scale reactions, product derivatization, and late-stage functionalization of natural products and drugs. Mechanistic studies implicate a sulfinyl radical in the PCET pathway of this transformation. Moreover, a proof of concept for an asymmetric protocol by a merger of acridine photocatalysis and cobalt catalysis was also reported.