Crystal structures of tetrakis(pyridine-4-thioamide-jN)bis(thiocyanato-jN)cobalt(II) monohydrate and bis(pyridine-4-thioamide-jN)bis(thiocyanato-jN)-zinc(II)

Abstract

Reaction of Co(NCS)2 and Zn(NCS)2 with 4-pyridinethioamide led to the formation of compounds with composition [Co(NCS)2(C6H6N2S)4]H2O (1) and [Zn(NCS)2(C6H6N2S)2] (2), respectively. The asymmetric unit of compound 1, consists of one cobalt(II) cation, two thiocyanate anions, four 4-pyridinethio-amide ligands and one water molecule whereas that of compound 2 comprises one zinc(II) cation that is located on a twofold rotation axis as well as one thiocyanate anion and one 4-pyridinethioamide ligand in general positions. In the structure of compound 1, the cobalt(II) cations are octahedrally coordinated by two terminal N-bonding thiocyanate anions and by the N atoms of four 4-pyridinethioamide ligands, resulting in discrete and slightly distorted octahedral complexes. These complexes are linked into a three-dimensional network via intermolecular N-H S hydrogen bonding between the amino H atoms and the thiocyanate S atoms. From this arrangement, channels are formed in which the water molecules are embedded and linked to the host structure by intermolecular O-H S and N-H O hydrogen bonding. In the structure of compound 2, the zinc(II) cations are tetrahedrally coordinated by two N-bonding thiocyanate anions and the N atoms of two 4-pyridinethioamide ligands into discrete complexes. These complexes are likewise connected into a three-dimensional network by intermolecular N-H S hydrogen bonding between the amino H atoms and the thioamide S atoms.