Spectroscopic studies of platinum halo-phosphine complexes

This thesis descibes n.m.r. spectroscopic studies of the preparation and reactions of some platinum (II) halo-phosphine and phosphane species. PtC1H(PEt₃)₂ reacts with PCl₃ in CD₂Cl₂ at 180 K to produce PtCl (PEt₃)₂ (PCI₂). On warming the solution, reversible protonation occurs to give [PtCl(PEt₃)₂(PCl₂H)]⁺. Further warming of the solution results in the formation of PtCi(PEt₃)₂(PH₂Cl₂). This species is thermally unstable above 260 K. Reaction of this species with HC1 or BCl₃ results in its dissociation to PtCl(PEt₃)₂(PH₂Cl) and HCl₂ or [BCl₄]⁻. Analogous behaviour was observed in the reaction of PtBrH(PEt₃)₂ with PBr₃ except that the initial six-coordinate product of oxidative addition at platinum was detected. The mechanism of formation of these products is discussed.Isolation of PtCl(PEt₃)₂(PCl₂) as an oil from the reaction of PtCIH(PEt₃)₂ with PCl₃ in the presence of Me₃N allowed its chemistry to be studied. A wide range of reactions was carried out with non-transition metal species to produce several interesting products. Reactions with transition metal complexes resulted in the formation of several hetero and homo-bimetallic species containing -PCl₂ or -PCI bridging groups.Attempts were made to produce a species containing a terminal -PF₂ group by the reaction of PtH₂(PCy₃)₂ with difluorophosphine species. Although unsucessful, the resulting cationic species contained -PF₂H groups and were spectroscopically characterised.An appendix containing n.m.r. parameters for complexes of iridium, platinum and rhodium is also included