One-dimensional structures of zinc(II) and cobalt(II) coordination complexes [Zn(NCS) 2(PPz)] n and [CoCl 2(PPz)] n (PPz=piperazine)

Abstract

The reaction of Zn(NO 3) 2·6H 2O with PPz hexahydrate (PPz=piperazine) and NH 4SCN in CH 3OH afforded the complex [Zn(NCS) 2(PPz)] n ( 1). The reaction of CoCl 2·6H 2O with PPz in CH 3OH afforded the complex [CoCl 2(PPz)] n ( 2). The PPz ligand in 1 is coordinated to the metal centers through both nitrogen atoms to form a 1-D zigzag-chain structure and the distorted tetrahedral coordination geometry at each zinc center is completed by a pair of N-bonded thiocyanate ligands. Compound 2 has an analogous 1-D zigzag-chain structure containing terminal chloro ligands. Important NCS⋯HN hydrogen-bonding interactions in compound 1 and NH⋯ClM and CH⋯ClM hydrogen-bonding interactions in compound 2 play a significant role in aligning the polymer strands in the crystalline solid.