oxyfunctionalization

Oxyfunctionalization refers to chemical transformations that introduce oxygen-containing functional groups into organic substrates, often by converting C-H or C-C bonds into C-O bonds or by adding oxygen across unsaturated motifs. It encompasses hydroxylation, epoxidation, carbonylation, and formation of alcohols, ketones, aldehydes, epoxides, and carboxylates.

Methods include enzymatic routes, especially oxygenases such as cytochrome P450 that perform selective hydroxylation of C-H bonds under mild conditions; monooxygenases. Chemocatalytic approaches use metal catalysts (Fe, Cu, Ru, Mn) with oxidants like O2, H2O2, peroxides, or hypervalent iodine to achieve hydroxylation, epoxidation, or oxidative cleavage. Photocatalytic and electrochemical methods enable oxyfunctionalization under milder conditions or with sustainable oxidants.

Selectivity: Regio- and stereoselectivity are crucial. Enzymatic systems often offer high site selectivity and enantioselectivity. Chemocatalytic systems rely on ligand design and reaction conditions. Challenges include over-oxidation, functional group incompatibility, and catalyst cost.

Applications: Used in late-stage functionalization of complex molecules, synthesis of pharmaceuticals and natural products, and development of alternative routes to alcohols and epoxides. Common transformations include C-H hydroxylation to alcohols, olefin epoxidation, and oxidation to carbonyl compounds.

Outlook: Oxyfunctionalization remains an active field linking biocatalysis, organometallic chemistry, and sustainable catalysis, with ongoing work to improve selectivity, efficiency, and substrate scope.