Periphery-functionalized organometallic dendrimers for homogeneous catalysis

The use of carbosilane based dendrimers as molecular scaffolds for the attachment of organomettallic Ni 'pincer' complexes that are active as a catalyst in the Kharasch addition reaction is described. It is shown that increasing steric crowding at the dendrimer periphery results in decreased catalyst activity, most likely as a consequence of an intramolecular redox process. Furthermore, preliminary investigations have shown that the application of this catalyst system in a continous process using a membrane reactor is possible.