Synthesis of polymer-supported rhodium(I)-1,3-bis(diphenylphosphino)propane moieties and their use in the heterogeneous hydrogenation of quinoline and benzylideneacetone

A p-styrenyl substituent attached to the ligand framework allows the diphos phine moiety -(C6H4)CH2-OCH2C(CH3)(CH2PPh2)(2) to be introduced as a pendan t group in cross-linked styrene/divinylbenzene matrixes via free-radical co polymerization. In conjunction with rhodium(I), the POLYDIPHOS material for ms an effective heterogeneous catalyst for the hydrogenation of benzylidene acetone to benzylacetone and of quinoline to a mixture-of 1,2,3,4-tetrahydr aquinoline, 5,6,7,8-tetrahydroquinoline, and decahydroquinoline. The homoge neous behavior of related 1,3-bis(diphenylphosphino)-propane rhodium comple xes is different in both activity and selectivity.