| Abstrakt: |
Hydrosilylation processes are still most often catalyzed using homogeneous complexes of transition metals (mainly platinum and rhodium). However, due to economic (high prices of precious metals), ecological (unacceptable presence of heavy metals in products), and technological (difficulties in removing catalysts from products and trying to recycle them) other catalytic systems are still being sought. In addition to the new earth-abundant TM-based catalysts (which are still not as effective as platinum complexes), heterogenized catalysts are increasingly being used. This chapter presents examples of such catalysts, which were obtained with the use of ionic liquids as a platform for the heterogenization of highly active Rh and Pt complexes. Ionic liquids (ILs) in these catalytic systems play different roles, as (i) a solvent dissolving the catalyst and an immobilizing agent (biphasic system), (ii) an immobilizing layer with a solid support (supported ionic liquid phase--SILP and solid catalysts with ILs layer SCILL), (iii) ligand in metal complexes, or (iv) complexes (halometallate ionic liquid). All of the above catalytic systems show high activity in hydrosilylation processes and also enable easy isolation and multiple use. [ABSTRACT FROM AUTHOR] |
