Synthesis and vibrational spectra of tin(II) isothiocyanate adducts with some O- and N-donor ligands

Abstract

Five new adducts of Sn(NCS)2 have been prepared and characterized: Sn(NCS)2•2L (L = 2,6-dimethyl-y-pyrone and N,N-dimethylacetamide), Sn(NCS)2•LL (LL = 1,10-phenanthroline and 2,2′-bipyridine), and Sn(NCS)(ox) (ox = 8-hydroxyquinolinate). By comparing their infrared and Raman spectra with those of SnX2•L (X = Cl, NCS; L = triphenylphosphine oxide), SnX2•2L (X = Cl, NCS; L = dimethylsulphoxide and pyridine-N-oxide), SnCl2•LL (LL = 1,10-phenanthroline and 2,2′-bipyridine), and SnCl(ox), assignments have been made for v(CN), v(CS), and δ(NCS) vibrations; these suggest the presence of N-bonded and —NCS— bridge-bonded thiocyanate groups. Molecular weight, conductivity, and X-ray powder diffraction data support the conclusion that the adducts with the oxygen donor ligands are molecular with only N-bonded thiocyanate groups. Adducts with the bidentate nitrogen donor ligands are polymeric and have —NCS— bridging and N-bonded thiocyanate.