Chapter 2 - The progress of chiral phosphine ligands in asymmetric iron catalysis

Abstract

In view of the inherent character of iron, such as low price and toxicity, environmentally benign, abundance, and so on, the development of new catalytic system based on iron is quite attractive. In the last few years, iron-catalyzed cross-couplings have proven to be critical in the pharmaceutical research. Most notably, iron is one of the very few effective base metal catalysts in industrial process that has been successfully applied to the preparation of medicine in kilogram scale, such as aliskiren (55.72kg), AZD6564 (9.8kg), cinacalcet (6.92kg), and so on. These results validate the potential and promising application of iron catalysis as a green catalyst instead of noble metal catalyst. Chiral iron catalyst–induced asymmetric transformation drew more and more attention and a series of transformations have been developed, including asymmetric reductions of carbonyl compounds and imines, epoxidations, additions to alkenes, nucleophilic additions to carbonyl compounds and derivatives, sulfa-Michael additions, cross-coupling reactions, cyclizations, ring-opening of epoxides, domino reactions, carbene transformation, and miscellaneous transformations. Although iron could ligate with nitrogen-, oxygen-, or phosphorus-based ligand, herein, we just give a summary on the advances of enantioselective transformation catalyzed by chiral iron complex with chiral phosphine ligand.