P Chiral Ligand

Compound 1 are P-chiral ligands developed by Knowles et al. This compound 1 forms a stable complex with rhodium, and the complex has been used as a catalyst for an asymmetric hydrogenation reaction. Particularly, the asymmetric hydrogenation reaction of α-acetylamino cinnamic acid derivative 2 is well known, and it provides L-amino acid derivative 3 with high optical purity. When this compound 3 is de-protected, L-DOPA, which is used for the treatment of Parkinsonism, can be obtained. Knowles won the Nobel Prize in Chemistry for his achievement of developing this asymmetric synthesis of L-DOPA in 2001.