Crystal structure of an alkoxide bridged dinuclear copper(II) complex: mild and selective oxidation of primary and secondary alcohols in water

Abstract

A water-soluble dinuclear Cu(II) complex, [Cu-2(OOCC6H4Br)(OCH3)(C10H8N2)(2)(ClO4)(2)] (4-bromobenzoic acid = HOOC-C6H4Br; 2-2'-bipyridyl = C10H8N2) was synthesized and characterized by X-ray crystallography. The complex was investigated as a selective catalyst for the mild oxidation of primary and secondary alcohols in the presence of hydrogen peroxide as oxidant at 70 degrees C in water. The complex proved to be an active catalyst for production of the corresponding aldehydes or ketones. Thus, cinnamyl alcohol, benzyl alcohol, 1-phenyl ethanol and 2-butanol were quantitatively oxidized in 6 h, using a low catalyst loading (1 mol%).