Planar‐Chiral Ferrocenes: Synthetic Methods and Applications

The first industrial applications of chiral ferrocenyl lignds of the Josiphos type have recently been disclosed. Compound 1a is used in the Rh-catalyzed, asymmetric hydrogenation of 2, a precursor in a new commercial synthesis of (+)-biotin. Ligand 1b is part of the highly active Ir catalyst used for the reduction of imine 3, from which the herbicide (S)-Metolachlor is made.