Group 12 metal coordination polymers built on a flexible hexakis(3-pyridyloxy)cyclotriphosphazene ligand: Effect of the central metal ions on the construction of coordination polymers

Abstract

The group 12 metal complexes [Zn-2(HPCP)Cl-4](n) (1), [Cd(HPCP)(2)Cl-2](n center dot)2H(2)O (2) and, [Hg-2(HPCP)Cl-4](n) (3), were synthesized by the reaction of hexakis(3-pyridyloxy)cyclotriphosphazene (HPCP) with a variety of metal salts (ZnCl2, CdCl2, HgCl2) in order to investigate the central metal ion effect on the formation of the coordination polymers. All of the isolated crystalline compounds were structurally determined by single crystal X-ray crystallography. Crystallographic analyses revealed that all the complexes crystallise in the monoclinic crystal system. The Zn(II) coordination compound is a 3D coordination polymer and, more interestingly, exhibits a 2-fold interpenetration, in which the single net has a uninodal 4-connected network with a diamondoid (dia) topology having the point symbol 6(6). The Cd(II) and Hg(II) complexes have the same two-dimensional (2D) layered structure with a uninodal 4-connected sql/ Shubnikov tetragonal plane net with {4(4).6(2)} topology. A coordination polymer of Hg(II) was obtained using the pyridyloxy cyclotriphosphazene ligand in this study for the first time. (C) 2017 Elsevier Ltd. All rights reserved.