The Unexpected Versatility of P4S3 as a Building Block in Polymeric Copper Halide Networks: 2,3-P, 1,2,3-P and all-P Coordination

Abstract

Layering solutions of P4S3 in CH2Cl2 with solutions of CuCl or CuI in CH3CN gives the coordination polymers (P4S3)3(CuCl)7 (1), (P4S3)2(CuCl)3 (2), (P4S3)(CuI) (3) and (P4S3)(CuI)3 (4), respectively, after slow diffusion. The yellow compounds were characterised by elemental analysis, 31P magic-angle spinning (MAS) NMR spectroscopy and single-crystal X-ray crystallography. The solid-state structures demonstrate the unexpected ligand versatility of the P4S3 molecule, which interacts through two, three, or even all of the phosphorus atoms with copper according to the nature of the copper halide. Compound 1 has a three-dimensional network in which linear and cylindrical infinite CuCl subunits coexist with diatomic CuCl building blocks. For the first time, all four P atoms of the P4S3 cage are involved in coordination with metal atoms. The 3D structure of 2 contains stacks of P4S3 that are interconnected by slightly undulated and planar [CuCl]n ribbons. Compound 3 is a one-dimensional polymer composed of alternating (CuI)2 rings and P4S3 bridges. The structure of 4 consists of undulated [CuI]n layers in which the P4S3 cage functions as a bridge within the layer, as well as a spacer between the layers. The 31P MAS NMR spectra obtained are in good agreement with the solid-state structures obtained crystallographically. Thus, analytically pure 3 and 4 show singlet peaks that correspond to uncoordinated P and quartets owing to coupling with 63Cu and 65Cu, respectively, whereas that of 1 contains quartets according to all-P coordination. The spectrum of 2 was obtained from a sample that still contained 40 % of 1.