Synthesis and Catalytic Activity of Rh(I) Phosphine Complexes Attached to Polymethylsiloxanes

Abstract

The largest portion of research on polymer attached homogeneous catalysts has dealt with the use of insoluble polymeric supports based on the polystyrene backbone.¹ Work on soluble polymeric supports has received less attention as has the use of inorganic materials. For example, work on metal complexes attached to the siloxane backbone has not been extensive. A patent has been issued describing the preparation and use of insoluble diphenylphosphinylethylsilsesquioxanes as supports for Pt and Pd catalysts.² Similar Rhodium containing siloxane polymers have been formed on the surface, of silica and their catalytic activity determined in the hydrogenation of olefins.^3-5 Advantages of using soluble siloxane polymer supports could arise because of their high thermal stability, as well as good coating and mechanical properties.⁶ We wish to report here the synthesis of various soluble and insoluble siloxane supports that contain diphenylphosphine functional groups with their Rhodium (I) complexes.⁶ The catalysts have been tested in the hydroformylation of 1-hexene.