General Electron-Donor-Acceptor Complex Mediated Thioesterification Reaction via Site-Selective C-H Functionalization using Aryl Sulfonium Salts

Comtemporary methods for synthesizing thioesters often necessitate expensive catalysts, and harsh conditions, making their synthesis from chemical feedstocks challenging. Herein, we report a concise metal-, photocatalyst-, and oxidant-free electron donar-acceptor (EDA) mediated synthesis of thioesters via site-selective C-H functionalization using aryl sulfonium salts (acceptor) with potassium thioacid salts (donor) under visible light irradiation. Our approach enables rapid access to thioesters from a wide variety of arenes including pharmaceutical and agrochemical compounds, as well as a diverse range of alkyl, aryl and heteroaryl potassium thioacid salts with excellent efficiency and regioselectivity. Mechanistic studies supported the formation of an EDA-complex and radical trapping experiments corroborated the involvement of a radical-based mechanism for the product formation.