A dicopper(II) complex, stabilized by the bis(tpa) ligand 1,2-bis[2-[bis(2-pyridylmethyl)aminomethyl]-6-pyridyl]ethane (6-hpa), [Cu (μ-OH)(6-hpa)] , was synthesized and structurally characterized. This complex catalyzed selective hydroxylation of benzene to phenol using H O , thus attaining large turnover numbers (TONs) and high H O efficiency. The TON after 40 hours for the phenol production exceeded 12000 in MeCN at 50 °C under N , the highest value reported for benzene hydroxylation with H O catalyzed by homogeneous complexes. At 22 % benzene conversion, phenol (95.2 %) and p-benzoquinone (4.8 %) were produced. The mechanism of H O activation and benzene hydroxylation is proposed.

Ad icopper(II) complex, stabilized by the bis(tpa) ligand 1,2-bis[2-[bis(2-pyridylmethyl)aminomethyl]-6-pyridyl]ethane (6-hpa), [Cu 2 (m-OH)(6-hpa)] 3+ ,w as synthesized and structurally characterized. This complex catalyzed selective hydroxylation of benzene to phenol using H 2 O 2 ,t hus attaining large turnover numbers (TONs) and high H 2 O 2 efficiency.T he TONa fter 40 hours for the phenol production exceeded 12000 in MeCN at 50 8 8Cu nder N 2 ,t he highest value reported for benzene hydroxylation with H 2 O 2 catalyzedb y homogeneous complexes.At22% benzene conversion, phenol (95.2 %) and p-benzoquinone (4.8 %) were produced. The mechanism of H 2 O 2 activation and benzeneh ydroxylation is proposed.

We have recently reported a copper(II)-superoxide complex supported by an N3-tridentate ligand (L(N3)), which exhibits a similar structure and reactivity to those of a putative reactive intermediate involved in the catalytic reactions of copper monooxygenases such as peptidylglycine α-hydroxylating monooxygenase (PHM) and dopamine β-monooxygenase (DβM). In this study, we have synthesised and characterised copper complexes supported by a related sulphur-containing ligand (L(N2S)) to get insight into the notable electronic effect of the sulphur donor atom in the reaction with cumene hydroperoxide, inducing efficient heterolytic O-O bond cleavage.

Methylthiophenoxyl radical plays an important role as the active form of galactose oxidase (GO), which catalyzes oxidation of a primary alcohol to the corresponding aldehyde. Although many metal(II)‐phenoxyl radical species have been reported, only a few studies have been reported on the properties of methylthiophenoxyl radical‐metal complexes. We have prepared the group 10 metal (Ni, Pd and Pt) complexes of a salen‐type ligand with a methylthio group at para‐position of the two phenolate moieties and characterized them by X‐ray crystal structure analyses and various spectroscopic methods in order to understand the role of the methylthio moiety in phenoxyl radical metal complexes. The corresponding p‐methoxy substituted derivatives have been also characterized for comparison. All the one‐electron oxidized group 10 metal methylthiophenolate complexes have a relatively localized radical site on one of the two phenolate moieties in comparison to the one‐electron oxidized complexes of p‐methoxy derivatives and exhibit different properties dependent on the central metal ions.