Recent Advances in Direct Single Oxygen Atom Insertion Into Organic Frameworks

Single-atom skeletal editing has emerged as a powerful strategy for precisely modifying molecular frameworks, enabling direct access to complex structures that are difficult to achieve through traditional synthesis. Within this field, the strategic incorporation of oxygen atoms is particularly valuable, as it can significantly alter a molecule's structure, polarity, and reactivity. This review summarizes the significant progress within this burgeoning area, delineating two primary reaction classes: (1) the formal insertion of oxygen into a carbon-carbon (C─C) single bond, and (2) its insertion into a carbon-heteroatom (C─X, where X = N, B) bond. A critical evaluation of diverse strategies, including strain-driven cleavage, functional group-directed activation, photoelectrochemical methods, and hypervalent iodine-mediated rearrangements, is presented, focusing on their reaction mechanisms, substrate scopes, and applications. By providing a comprehensive overview of the progress and developments in oxygen atom insertion, this review aims to serve as a practical guide for the growing field of single-atom skeletal editing and to inspire future innovations in synthesis.