Aromatic Hydroxylation by H₂O₂ and O₂ Catalyzed by a μ‐Oxo Diiron(III) Complex

Abstract

An excellent functionalized enzyme model for the active site of methane monooxygenase and ribonucleotide reductase is represented by the μ‐ace‐tato‐ and μ‐oxo‐bridged diiron complex 1. Reaction with H2O2 or O2 in the presence of ascorbate leads to hydroxylation of one phenyl ring to a phenol. This then coordindates to the metal center with formation of a mononuclear complex.

Molecular iron complexes as catalysts for selective C–H bond oxygenation reactions

“…185 Intramolecular ortho-hydroxylation is observed after addition of tBHP and mechanistic investigations revealed that these systems are potent functional models, which support a better understanding of the enzymes' reactivity. [185][186][187] …”

μ-Oxo-bridged diiron(iii) complexes of tripodal 4N ligands as catalysts for alkane hydroxylation reaction using m-CPBA as an oxidant: substrate vs. self hydroxylation

“…66 Interestingly, several diiron(III) complexes catalyzes intra-molecular aliphatic 67 and aromatic oxidation reactions, where the phenyl group is usually oxidized using various oxidants. [68][69][70][71][72] Although, various m-oxo-bridged nonheme diiron(III) complexes that mimic the functions of diiron enzymes have been reported earlier, the design and study of diiron(III) complexes would enhance the understanding further to utilize the complexes as excellent catalysts for the oxidation of organic substrates, particularly for alkane functionalization and alkene epoxidation reactions. Moreover, the factors determining the selectivity as well as efficiency of the catalysts remain still unclear.…”

Aromatic hydroxylation using an oxo-bridged diiron(iii) complex: a bio-inspired functional model of toluene monooxygenases

“…Moreover, aromatic hydroxylation mediated by oxo-bridged diiron(III) complexes is sparsely reported in the literature. 10,21 The oxo-bridged diiron(III) complex based on an EDTA based ligand has been shown to hydroxylate the coordinated phenyl ring. 21 However, the diferric complex was found to disintegrate into a mononuclear(III) product at the end of the reaction.…”

“…10,21 The oxo-bridged diiron(III) complex based on an EDTA based ligand has been shown to hydroxylate the coordinated phenyl ring. 21 However, the diferric complex was found to disintegrate into a mononuclear(III) product at the end of the reaction. Very recently, Wang et al…”