Crystal structure of di-aqua-(3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosa-ne)copper(II) dichloride tetra-hydrate.

The crystal structure of the novel hydrated CuII salt, [Cu(L)(H2O)2]Cl2·4H2O (L = 3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of the [Cu(L)(H2O)2]2+ cation (completed by crystallographic inversion symmetry), one chloride anion and two lattice water mol-ecules. The copper(II) atom exists in a tetra-gonally distorted octa-hedral environment with the four N atoms of the macrocyclic ligand in equatorial and two O atoms from water mol-ecules in axial positions. The latter exhibit a long axial Cu-O bond length of 2.7866 (16) Å due to the Jahn-Teller distortion. The macrocyclic ring adopts a stable trans-III conformation with typical Cu-N bond lengths of 2.0240 (11) and 2.0441 (3) Å. The complex is stabilized by hydrogen bonds formed between the O atoms of coordinated water mol-ecules and the NH groups as donors, and chloride anions as acceptors. The chloride anions are further connected to the lattice water solvent molecules through O-H⋯Cl hydrogen bonds, giving rise to a three-dimensional network structure.