The structure of N- meso-(6,8,8,14,16,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,13-diene)nickel(II) chloro(isothiocyanato)zincate(II)

Abstract

A yellow compound which was crystallised from a solution of (6,8,8,14,16,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,13-diene)bis(isothiocyanato)nickel(II) in aqueous zinc(II) chloride has cations with singlet ground state nickel(II) in square-planar coordination by the nitrogen atoms of the macrocycle. The asymmetric unit has two similar cations. The N 4 group of one cation is near coplanar (r.m.s. displacements ±0.009(1) Å, with Ni displaced by 0.048(1) Å from this plane) while the other cation has significant tetrahedral twisting of the N 4 group (r.m.s. displacements of N atoms ±0.126(2) Å, with Ni displaced by 0.027(2) Å from this plane). The mean Ni–N distances are Ni–N amine = 1.950(6) and Ni–N imine = 1.897(6) Å. Both cations have N- meso configurations with saddle conformations, with the substituted chelate rings in boat conformations tilted to one side of the NiN 4 ‘plane’ and the unsubstituted chelate rings tilted to the other side, one in a boat conformation and the other with the central methylene group disordered, the components forming boat {s.o.f. 0.70(1) and 0.74(1) for the two cations} and chair conformation chelate rings. The counter-ions have tetrahedrally coordinated zinc(II) ions, one as [ZnCl 2(NCS) 2] 2− ions and the other with one ligand site with disordered Cl − {s.o.f. 0.78(1)} and NCS − ligands, i.e. with disordered [ZnCl 2(NCS) 2] 2− and [ZnCl(NCS) 3] 2− ions, with an overall composition of [Ni( trans-Me 6[16]diene)][ZnCl 1.9(NCS) 2.1].