All of the initial work on the anchored homogeneous catalysts used Rh(DiPamp) complexes anchored to the support by the heteropoly acid, phosphotungstic acid (PTA). Eventually, complexes having a number of other chiral and achiral ligands were also anchored to different support materials. A number of chiral Rhodium complexes anchored on alumina by PTA were used for the enantioselective hydrogenation of methyl 2-acedamidoacrylate (1). The data in the Table lists the rates and ee data for these reactions as well as the corresponding data obtained using the homogeneous catalyst. The anchored catalysts were not pre-hydrogenated so the data are presented for the first and third use of these species.

Table. Rate data for the hydrogenation of methyl 2-acetamido acrylate (1) over homogeneous and anchored Rh(ligand)(COD) catalysts.

A number of other chiral ligands were also used in anchored complexes involved in the enantioselective hydrogenation of various prochiral substrates as described in the following section. Some achiral ligands have been used to prepare anchored catalysts used for the hydrogenation of substrates such as 1-hexene, carvone and a series of aldehydes. The chemical names, common names and sources of these ligands are listed below.