Palladium complex immobilised on zirconium-phosphite: Characterisation by 31P MAS NMR and TEM and behaviour towards reducing agents
Résumé
The immobilisation of triphenylphosphine–phosphonic acid complexed to palladium dichloride on a zirconium-phosphite network is achieved by mixing a zirconium(IV) salt, phosphorous acid (H3PO3) and dichlorobis(4-(diphenylphosphinyl)phenylphosphonic acid)palladium 2 to yield the amorphous material 3. The complementary informations obtained by both 31P solid-state NMR (1D and 2D experiments) and Transmission Electron Microscopy analyses (EDS scanning) stated of a homogeneous distribution of palladium in the zirconium-phosphite network allowing us to propose a model for the structure of material 3. The treatment of compounds 3 with a reducing agent (triethyl silane or hydrazine) yields well defined aggregates (palladium oxide or metallic palladium) on the surface of the material that were characterized by TEM.