Design Concepts for Developing Highly Efficient Chiral Bisphosphine Ligands in Rhodium-Catalyzed Asymmetric Hydrogenations

Several efficient asymmetric hydrogenations catalyzed by chiral bisphosphine-rhodium complexes were developed with the modification of bisphosphine ligands on the basis of our designing concept. 1. Introduction 2. The Respective Control Concept. A Proposal for the Development of Highly Efficient Chiral Bisphosphine Ligands 2.1. Preliminary Considerations 2.2. The Design of the Highly Efficient Bisphosphine Ligand BCPM 2.3. Experimental Confirmation of the Respective Control Concept 3. Application of the Designing Concept to C ₂-Symmetric Bisphosphines 3.1. Development of Modified DIOP Ligands 3.2. Application to 1,2- and 1,3-Substituted Bisphosphines 3.3. Newly Designed 1,3-Substituted Bisphosphines 4. Application to the Practical Asymmetric Syntheses of Optically Active Medicines 5. Mechanistic Considerations of the Basis of the Correlation between Chirality of the Catalyst and Absolute Configuration of the Hydrogenation Product 5.1. Mechanism of Asymmetric Hydrogenation of Olefins 5.2. Mechanism of Asmmetric Hydrogenation of Ketones 6. Conclusion