VERSATILE POLYMER-BOUND HYDROGENATION CATALYSTS - RHODIUM(I)-CATALYZED HYDROGENATION

The bidentate ligand anthranilic acid has been anchored to polystyrene beads (Amberlite XAD-4) and the Rh(I) complex has been prepared. The polymer is a hydrogenation catalyst of exceptional activity, long-term stability, and considerable insensitivity to poisoning. Hundreds of catalytic cycles per metal atom are demonstrated without substantial loss of activity. The rhodium catalyst reduces a variety of olefinic and aromatic hydrocarbons and carbonyl, nitrile, and nitro functional groups. Catalytic activity depends upon retention of beads; if fragmentation occurs, the activity is considerably diminished. ESCA studies clearly demonstrate the rhodium to have a +1 formal oxidation state. Copyright © 1979, American Chemical Society. All rights reserved.