Formation of the unusual cluster Cu4(μ4-OH)(μ-(CF3)2pz)4(μ-OOCPh)2(μ-OH)2(OH2)(Et3NH)[O(CH2Ph)2]2 in the thermolysis of a copper μ-aqua complex with bridging pyrazolate and acetate ligands in dibenzyl ether in the presence of atmospheric oxygen

Abstract

A room temperature reaction of cupric acetate dihydrate with 3,5 bis(trifluoromethyl)pyrazole ((CF 3 ) 2 pzH) in chloroform in the presence of triethylamine gave a complex of the formula [Cu 2 (μ (CF 3 ) 2 pz) 2 (μ OH 2 )(OC(Me)OHNEt 3 )(OH 2 )(HCCl 3 )(OOCMe)(μ OOCMe)] 2 (2). Heating of this complex at 180°C in dibenzyl ether (DBE) in air yielded the tetranuclear pyrazolate benzoate cluster Cu 4 (μ 4 OH)(μ (CF 3 ) 2 pz) 4 (μ OOCPh) 2 (μ OH) 2 (OH 2 )(Et 3 NH)[O(CH 2 Ph) 2 ] 2 . It was suggested that such complexes can be intermediates in the liquid phase oxidation of DBE with atmospheric oxygen in the presence of copper com plexes containing pyrazolate bridges.