Crystal structure of (4,4'-bipyridyl-κN)bis-[N-(2-hydroxy-ethyl)-N-iso-propyl-dithio-carbamato-κ2S,S']zinc(II)-4,4'-bipyridyl (2/1) and its isostructural cadmium(II) analogue

The title structures, [M(C6H12NOS2)2(C10H8N2)]·0.5C10H8N2, for M = Zn, (I), and Cd, (II), feature terminally bound 4,4'-bipyridyl ligands and non-coordinating 4,4'-bi-pyridyl mol-ecules, with the latter disposed about a centre of inversion. The coordination geometry about the metal atom is defined by two non-symmetrically chelating di-thio-carbamate ligands and a pyridyl N atom. The NS4 donor sets are distorted but, approximate to trigonal bipyramidal in each case. In the crystal, hy-droxy-O-H⋯O(hy-droxy) and hy-droxy-O-H⋯N(pyrid-yl) hydrogen bonds between the zinc-containing mol-ecules lead to a supra-molecular layer parallel to (100). The three-dimensional architecture arises as the layers are linked via methine-C-H⋯S, pyridyl-C-H⋯O(hy-droxy) and π-π [inter-centroid distance between coordinated pyridyl rings = 3.6246 (18) Å] inter-actions. Channels along the c-axis direction are occupied by the non-coordinating 4,4'-bipyridine mol-ecules, which are held in place by C-H⋯π(chelate ring) contacts.