synthesis and crystal structures of three new hetero-binuclear hg(ii)-cu(ii) schiff base complexes

new hetero-binuclear hg-cu schiff base complexes were prepared by reaction of 2,2'-[1,1'-(2,2-‎dimethylpropane-1,3-diyldinitrilo)-diethyldyne]diphenolato}copper(ii) (cul1) and 6,6'-x-2,2'-[(2,2-‎dimethylpropane-1,3-diyl)bis(nitrilomethanylylidene)]diphenolato copper(ii) [(x = ethoxy (cul2) and ‎methoxy (cul3)], with hgcl2 to give [cu(l1)hgcl2] (1), [cu(l2)hgcl2] (2), and [cu(l3)hgcl2] (3), ‎respectively. in the precursor cu(ii) complexes (cul1-cul3), the coordinated phenolic oxygen atoms and ‎those of the substituents at 3,3'-positions (in 2 and 3) on aromatic ring can act as additional site of ‎coordination to hgcl2 as metallo-ligand to make heterobinuclear cu-hg complexes. the h2l1, h2l2, and h2l3 ‎schiff base ligands were characterized by elemental analyses, 1h nmr and ft ir techniques. the related ‎binuclear cu-hg complexes were characterized by elemental analyses and single-crystal x-ray diffraction. the ‎main coordination sites for the hgcl2 unit are phenolic oxygen atoms and there are also short intramolecular ‎hg…o (methoxy, and ethoxy segments) contacts in 2 and 3. the crystal packing of 3 shows one-dimensional ‎extended chains along the b-axis through pair of centro-symmetric c–h…cl interactions. the new complexes ‎crystallize in pbca (1), p21/n (2), and p21/c (3) space groups. ‎