Synthesis, characterizations and crystal structures of new antimony (III) complexes with dithiocarbamate ligands

Abstract

Eight new antimony (III) complexes containing dithiocarbamate ligands (R 2NCS 2) 2SbBr [R 2NCS 2 = OC 4H 8NCS 2 ( 1), C 2H 5NC 4H 8NCS 2 ( 2), Me 2NCS 2 ( 3), C 4H 8NCS 2 ( 4)] and (R 2NCS 2) 3Sb[R 2NCS 2 = C 5H 10NCS 2 ( 5), Bz 2NCS 2 ( 6), Et 2NCS 2 ( 7), (HOCH 2CH 2) 2NCS 2 ( 8)] have been synthesized by the reactions of antimony (III) halides with dithiocarbamate ligands in 1:2 or 1:3 stoichiometries. All the complexes have been characterized by elemental analysis, melting point as well as spectral [IR and NMR ( 1H and 13C)] studies. The crystal structures of complexes 1, 5 and 8 have been determined by X-ray single crystal diffraction, and their electrochemical character has also been studied. The structure of complex 1 shows that the five-coordinated antimony (III) atom adopts a distorted trigonal bipyramidal geometry. Furthermore, the supramolecular structure of 1 consists of a one-dimensional linear molecular chain which is built up by intermolecular Sb⋯S and S⋯S weak interactions. In complex 5, the central antimony atom is six-coordinated with a distorted octahedral geometry and the supramolecular structure is constructed by C–H⋯S weak hydrogen bonds. The structure of complex 8 is stabilized by strong intermolecular hydrogen bonds between the ethanolic hydrogens (O–H).