Diphosphine Ligands for Rh Catalyzed Asymmetric Hydrogenation

2 Chiral 1,4-Diphosphine Ligands for Rh-Catalyzed Asymmetric Hydrogenation 

Ligand Substrate S/C ratio Reaction conditions % ee (config.) References 

Considering that a metal DIOP complex is conformationally fiexible and the stereo genic centers may be too far from the substrate, Kagan synthesized a modified DIOP ligand 28 in which the stereogenic centers are closer to the phosphorus atom [31]. 

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