Platinum(II) and palladium(II) complexes of some chelating poly-fluoroalkyldithioethanes

Abstract

Platinum(II) halide complexes of the chelating ligands CF₃SCH₂CH₂SCF₃, CF₃SCHMeCH₂SCF₃, and C₆F₅SCH₂CH₂SC₆F₅ and platinum(II) and palladium(II) complexes of CF₃SCH₂CH₂SCH₃, CH₃SCF₂, CH₂SCH₃, CH₃SCH(CF₃)CH₂SCH₃, CH₃SCH(CF₃)CH(CF₃)SCH₃, and C₆F₅SCH₂CH₂SCH₃ are described. N.m.r. spectroscopy shows the presence of isomers for each complex with rapid ring-conformational changes but slow inversion at sulphur on an n.m.r. time scale. Detailed ¹⁹F n.m.r. studies allow specific isomers to be identified in many cases. Low-temperature ¹⁹F n.m.r. studies on [Ptl₂{CH₃SCH(CF₃)CH(CF₃)SCH₃}] show a barrier to ring-conformational changes, the first such barrier observed for five-membered chelate rings.