| Summary: | Reactions of VCl<sub>3</sub> with 1,2-Bis[(4-methylphenyl)imino]acenaphthene (4-Me-C<sub>6</sub>H<sub>4</sub>-bian) or 1,2-Bis[(2-methylphenyl)imino]acenaphthene (2-Me-C<sub>6</sub>H<sub>4</sub>-bian) in air lead to the formation of [VOCl<sub>2</sub>(R-bian)(H<sub>2</sub>O)] (R = 4-Me-C<sub>6</sub>H<sub>4</sub> (<b>1</b>), 2-Me-C<sub>6</sub>H<sub>4</sub> (<b>2</b>)). Thes complexes were characterized by IR and EPR spectroscopy as well as elemental analysis. Complexes <b>1</b> and <b>2</b> have high catalytic activity in the oxidation of hydrocarbons with hydrogen peroxide and alcohols with <i>tert</i>-butyl hydroperoxide in acetonitrile at 50 °С. The product yields are up to 40% for cyclohexane. Of particular importance is the addition of 2-pyrazinecarboxylic acid (PCA) as a co-catalyst. Oxidation proceeds mainly with the participation of free hydroxyl radicals, as evidenced by taking into account the regio- and bond-selectivity in the oxidation of n-heptane and methylcyclohexane, as well as the dependence of the reaction rate on the initial concentration of cyclohexane.
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