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

Eight new antimony (III) complexes containing dithiocarbamate ligands (R2NCS2)2SbBr [R2NCS2 = OC4H8NCS2 (1), C2H5NC4H8NCS2 (2), Me2NCS2 (3), C4H8NCS2 (4)] and (R2NCS2)3Sb[R2NCS2 = C5H10NCS2 (5), Bz2NCS2 (6), Et2NCS2 (7), (HOCH2CH2)2NCS2 (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).

Graphical abstractA series of antimony (III) complexes with dithiocarbamate ligands (R2NCS2)2SbBr [R2NCS2 = OC4H8NCS2 (1), C2H5NC4H8 NCS2 (2), Me2NCS2 (3), C4H8NCS2 (4)] and (R2NCS2)3Sb [R2NCS2M = C5H10NCS2 (5), Bz2NCS2 (6), Et2NCS2 (7), (HOCH2CH2)2NCS2 (8)] have been synthesized. These complexes have been characterized by elemental analysis, IR, 1H and 13C NMR spectra.Figure optionsDownload full-size imageDownload as PowerPoint slide