Synthesis and structure of a complex of copper(I) with l-cysteine and chloride ions containing CuS nanoclusters.

The title hydrated copper(I)-l-cysteine-chloride complex has a polymeric structure of composition {[Cu(CysH)Cl]·HO} [CysH = HOCCH(NH )CHS or CHNOS], namely, poly[[tetra-μ-chlorido-deca-μ-chlorido-di-chlorido-hexa-kis-(μ-l-cysteinato)hexa-deca-copper] polyhydrate]. The copper atoms are linked by thiol-ate groups to form CuS nanoclusters that take the form of a tetra-kis cubocta-hedron, made up of a Cu cubo-octa-hedral subunit that is augmented by six sulfur atoms that are located symmetrically atop of each of the Cu square units of the Cu cubo-octa-hedron. The six S atoms thus form an octa-hedral subunit themselves. The exterior of the CuS sphere is decorated by chloride ions and trichlorocuprate units. Three chloride ions are coordinated in an irregular fashion to trigonal Cu subunits of the nanocluster, and four trigonal CuCl units are bonded each of their chloride ions to a copper ion on the CuS sphere. The trigonal CuCl units are linked CuCl bridges covalently connected to equivalent units in neighboring nanoclusters. Four such connections are arranged in a tetra-hedral fashion, thus creating an infinite diamond-like net of CuSCl(CuCl) nanoclusters. The network thus formed results in large channels occupied by solvent mol-ecules that are mostly too ill-defined to model. The content of the voids, believed to be water mol-ecules, was accounted for reverse Fourier-transform methods using the SQUEEZE algorithm [Spek (2015 ▸). C, 9-18]. The protonated amino groups of the cysteine ligands are directed away from the sphere, forming N-H⋯Cl hydrogen bonds with chloride-ion acceptors of their cluster. The protonated carb-oxy groups point outwards and presumably form O-H⋯O hydrogen bonds with the unresolved water mol-ecules of the solvent channels. Disorder is observed in one of the two crystallographically unique [Cu(CysH)Cl] segments for three of the six cysteine anions.