Formation of the unusual cluster Cu4( Delta m4-OH)( Delta m-(CF3)2pz)4( Delta m-OOCPh)2( Delta m-OH)2(OH2)(Et3NH)[O( CH2Ph)2]2 in the thermolysis of a copper Delta m-aqua complex with bridging pyrazolate and acetate ligands in dibenzyl ether in the presence of atmospheric oxygen

A room-temperature reaction of cupric acetate dihydrate with 3,5-bis(trifluoromethyl)pyrazole ((CF3)2pzH) in chloroform in the presence of triethylamine gave a complex of the formula [Cu2( Delta *m-(CF3)2pz)2( Delta *m-OH2)(OC(Me)OHNEt3)(OH2)(HCCl3)(OOCMe)( Delta * m-OOCMe)]2 (2). Heating of this complex at 180 degree C in dibenzyl ether (DBE) in air yielded the tetranuclear pyrazolate-benzoate cluster Cu4( Delta *m4-OH)( Delta *m-(CF3)2pz)4( Delta *m-OOCPh)2( Delta *m-OH)2(OH2)(Et3NH)[O( CH2Ph)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 complexes containing pyrazolate bridges.