Dipotassium di-mu-isothiocyanato-kappa4N:S-bis[(N-salicylidene-DL-valinato-kappa3O,N,O')cuprate(II)

Abstract

The title compound, K(2)[Cu(2)(NCS)(2)(C(12)H(13)NO(3))(2)], consists of two K(+) cations and (N-salicylidene-D-valinato)copper(II) and (N-salicylidene-L-valinato)copper(II) coordination units connected through three-atom thiocyanate (mu-NCS) bridges into a centrosymmetric dianion. The Cu(II) atom adopts a square-pyramidal coordination, with three donor atoms of the tridentate Schiff base and one N atom of the bridging ligand (mu-NCS) in the basal plane. The axial position is occupied by the thiocyanate S atom of a symmetry-related ligand at an apical distance of 2.9332 (10) A. Coulombic interactions between six-coordinated K(+) ions and the heteroatoms of neighbouring dimeric anions leads to the formation of one-dimensional chains of molecules parallel to [010]. The superposition of the normals of the pyramidal base planes in a direction close to [001] indicates possible pi-pi interactions between neighbouring units.