A linear cyclic oximate-bridged tetracopper(II) complex

The crystal structure of the title complex, tetrakis[mu -6-amino-3-methyl-4 -azahex-3-en-2-one oximato(1-)-kappa N-4,N',N " :O]tetracopper(II) tetraper chlorate 0.6-hydrate, [Cu-4(C6H12N3O)(4)](ClO4)(4).0.6H(2)O, shows the cati on to be an oximate-bridged tetramer composed of four 6-amino-3-methyl-4-az ahex-3-en-2-one oxime ligands and four copper(II) ions and to have crystall ographically imposed (4) over bar symmetry. Each Cu II atom is four-coordin ated by the three N atoms of one oxime ligand and by the O atom of another oxime ligand in a distorted square-planar geometry.