[OH-TEMPO]+[NO3]–: A Metal-Free and Cost-Effective Catalyst for Aerobic Oxidation of Alcohols

Abstract

The development of sustainable methods for the oxidation of alcohols to aldehydes or ketones remains an important goal in synthesis. In this work, we synthesized a series of nitrate-bearing oxoammonium salts and demonstrated their efficiency as metal-free catalysts for the aerobic oxidation of alcohols. These catalysts operate under mild conditions and exhibit a broad substrate scope, efficiently oxidizing both primary and secondary alcohols. The catalytic system performs effectively on a gram scale with industrially relevant substrates, providing a valuable alternative to current protocols. The system operates via a hydride-transfer mechanism and a self-sustained NOₓ-mediated redox cycle, with molecular oxygen as the terminal oxidant.