Selective catalytic oxygen functionalization reactions of C—H bonds are a very challenging class of reactions in organic chemistry. Compared with tranditional metal complex catalysts, enzymes exhibit certain advantages in terms of selectivity and activity. Amongest them, peroxygenases are able to catalyze the oxidative functionalization of C—H bonds by direct use of H₂O₂ as a co-substrate. Peroxygenases combine the catalytic versatility of P450 monooxygenases without relying on coenzymes and their regenerative systems for cofactors. Therefore, peroxygenases have attracted considerable attention in organic synthesis. However, a bottleneck in the practical application of peroxygenase is that, like all heme-dependent enzymes, peroxygenase is sensitive to H₂O₂, and higher concentration of H₂O₂ in the reaction system will cause oxidative decomposition of ferrous heme, resulting in the enzyme inactivation. To overcome this, regulating the concentration of H₂O₂ in the reaction is particularly important for the efficient use of peroxygenase. This paper outlines a variety of methods used for in situ generation of H₂O₂ to drive peroxygenases reported in recent years. The pros and cons of biocatalysis, photocatalysis and electrocatalysis used for high atom-efficient H₂O₂ generation are comprehensively analyzed. This review paper is expected to provide a reference for promoting the application of peroxygenases in organic synthesis.

Key words: peroxygenase, H₂O₂ in situ generation, C—H bond oxyfunctionalization, biocatalysis, organic synthesis