Anchored homogeneous catalysts: The best of both worlds

Homogeneous catalysts can be anchored to a number of different support materials using heteropoly acids as the anchoring agents. This technique can be used to anchor preformed complexes thus eliminating the need to modify the ligand to accomplish the 'heterogenization'. These anchored catalysts are stable in a range of solvents with little, if any, loss of the complex during the reaction. They are generally as active and selective as the homogeneous analogs and are particularly effective with the chiral complexes commonly employed today for enantioselective hydrogenations. These catalysts have been used for multiple batch and continuous hydrogenations with TON's of 10,000 and greater and TOF's as high as 650 hr(-1).