Developing asymmetric variants for enantioselective oxidations: A review

Abstract

Asymmetric oxidation reactions are pivotal in modern organic chemistry, facilitating the synthesis of enantiomerically enriched molecules with significant synthetic and industrial relevance. This review encapsulates advancements in asymmetric oxidation methodologies, emphasizing catalytic systems, ligand design strategies, notable breakthroughs recently, and mechanistic insights. The focus is on metal-catalyzed, organocatalytic, and emerging electrochemical techniques, illustrated through examples such as allylic oxidations, sulfoxidations, epoxidations, and innovative C-H oxidation strategies. It also addresses the challenges and future prospects aimed at enhancing stereoselectivity and substrate versatility in asymmetric oxidations. The significance of enantioselective oxidation reactions is underscored as they are essential for introducing oxygen-containing functional groups in organic molecules. The review discusses effective strategies for achieving enantioselectivity through various methods, including metal-catalyzed, organocatalytic, and biocatalytic approaches that provide high enantiocontrol. Transformations highlighted include asymmetric epoxidation, dihydroxylation, Baeyer-Villiger oxidation, sulfoxidation, and allylic oxidation, focusing on catalyst design, reaction mechanisms, and practical synthetic applications. Additionally, emerging trends in photoredox catalysis, enzymatic oxidation, and electrochemical methods reflect the dynamic progress in asymmetric oxidation, showcasing its crucial role in the stereoselective synthesis of complex molecules.