Dalton communications. Different acetate bonding modes and the smallest monoatomic Cu–O–Cu bridge angle in [Cu3(O2CMe)4(H2O)(bipy)3][PF6]2(bipy = 2,2′-bipyridine)

Abstract

The reaction of 2,2′-bipyridine (bipy) with [Cu₂(O₂CMe)₄(H₂O)₂] in ethanol follwed by NH₄PF₆ yields an unique trinuclear copper(II) species, [Cu₃(O₂CMe)₄(H₂O)(bipy)₃][PF₆]₂, the crystal structure of which shows the smallest monoatomic acetate bridge Cu–O–Cu angle of 92.9(1)° and four different acetate co-ordination modes; in methanol glass at 77 K it exhibits an X-band ESR spectrum characteristic of a strongly coupled dicopper(II) unit and a normal copper(II) centre.