catena-Poly[[chloridotris(1,3-thiazolidine-2-thione-κS)cadmium(II)]-μ-chlorido]

In the structure of the title compound, [CdCl2(C3H5NS2)3]n, the CdII atom is coordinated by three S and three Cl atoms in a mer arrangement.


Structure description
1,3-Thiazolidine-2-thione (tzdSH: C 3 H 5 NS 2 ), is a well-known heterocyclic thione/thiol ligand. Crystallographic studies and investigations of its modes of coordination have been reported (Saithong et al., 2007). We are interested in the coordination behaviour and structure of tzdSH complexes with Cd II chloride. The synthesis is accompanied by a transformation of the tzdSH (tzdSH: C 3 H 5 NS 2 , thiol form) into a tzdt ligand (tzdt: C 3 H 5 NS 2 , thion form). A similar transformation was described previously by Saithong et al. (2014). Metal complexes of thiones and thionates were reviewed by Raper (1997).
The above structural studies show that thiones coordinate to cadmium (II) via the sulfur atom. To further investigate the structural aspects of such complexes, we report in this work a complex with a Cd II :thione ratio of 1:23. The asymmetric unit consists of a cadmium (II) ion bonded to three 1,3-thiazolidine-2-thione moieties via the exocyclic sulfur atom and two Cl atoms (Fig. 1). The Cd-S and Cd-Cl bond lengths are in the range 2.7004 (11)-2.7347 (13) and 2.5430 (12)-2.7258 (16) Å , respectively. The bond lengths are slightly different from those reported in the literature [Cd-S = 2.604 Å and Cd-Cl = 2.7105 Å ; Bell et al., 2004]. This may be due to the intramolecular hydrogen bonds observed in the crystal structure.
In the crystal, one of Cl À anions connects two neighbouring Cd II centers leading to polymeric chains. No hydrogen bonds are observed between the chains. The structure of the compound can be described as parallel chains running along the a-axis direction. The conformation of the chains is stabilized by N-HÁ Á ÁCl hydrogen bonds (Table 1, Fig. 2).

Figure 2
Packing diagram of the title compound. N-HÁ Á ÁCl hydrogen bonds are show as light blue dashed lines.

Figure 1
The asymmetric unit of title compound with displacement ellipsoids drawn at the 50% probability level.  appeared after the light yellow filtrate had been kept at room temperature for two days (yield 75%).

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2.

data-2
IUCrData (2020). 5, x201423 Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. Refinement. H atoms were refined using a riding model with N-H = 0.86 Å or C-H = 0.97 Å and U(H)=1.2U eq (C,N).