Crystal and molecular structure and spectroscopic properties of diaquabis(N-acetyl-D,L-phenylglycinato)bis(imidazole)copper(II)

The diaquabis(N-acetyl-D,L-phenylglycinato)bis(imidazole)copper(II) compound has been prepared and structurally and spectroscopically characterized. The structure consists of monomeric units, in which the copper atom presents a tetragonally distorted octahedral coordination with two centrosymmetrically related carboxyl oxygens and imidazole nitrogen atoms in the square plane. Two long contacts in the out-of-plane axial positions, involving the two water molecules, complete the coordination, giving rise to a CuN2O2O′2 chromophore. In the imidazole adducts of the copper(II) compounds of the N-substituted amino acids the metal(II) ion was until now found in an essentially square-planar geometry with a CuN2O2 chromophore. Magnetic and spectroscopic results also confirm a tetragonally distorted octahedral coordination geometry of the copper(II) ion with (xy)2(xz,yz)4(z2)2(x2-y2), 2Ag (Ci symmetry) ground state. © 1993.