Late-Stage Oxygenation in Organic Synthesis: From Innate Reactivity to Directed Selectivity in Complex Settings

Late-stage oxygenation (LSO) has emerged as a transformative strategy in modern synthetic chemistry, enabling the precise modification of complex, densely functionalized molecules. Driven by the growing demand for efficient, selective, and sustainable methods in pharmaceutical, agrochemical, and materials science, recent advances have expanded the scope and utility of this approach. Breakthroughs in the design of selective oxidants, biocatalytic platforms, and photoredox methodologies have redefined the possibilities for molecular diversification and functionalization at advanced synthetic stages. This review consolidates the conceptual foundations of LSO with cutting-edge developments across chemical and enzymatic domains, highlighting both practical applications and mechanistic insights. By integrating these perspectives, we aim to provide a comprehensive resource that will guide practitioners across disciplines, from those newly entering the field to experts seeking to harness the latest innovations.