Electrochemical Sulfinylation-Driven Skeletal Rearrangement of Baylis-Hillman Adducts

Abstract

We report an electrochemical sulfinylation protocol that drives a skeletal rearrangement of Baylis-Hillman adducts, enabling the late-stage synthesis of methyl (Z)-3-(aryl/heteroaryl)-2-[(aryl/alkyl)sulfinyl]methyl acrylates. The transformation merges sulfenylation with a framework rearrangement, proceeds in an undivided cell with inexpensive KI as electrolyte and redox mediator, and requires no metals or external oxidants. Under mild conditions, the method delivers good to excellent yields across diverse substrates and can be scaled efficiently. Control experiments, EPR spectroscopy, and ¹⁸O-labeling confirm a radical pathway with intramolecular oxygen transfer, while DFT studies delineate the stepwise mechanism. This work establishes a green and general strategy for accessing sulfoxide-containing scaffolds through electrochemically induced skeletal reorganization.