Catalytic asymmetric carbon-carbon bond-forming reaction utilizing rare earth metal complexes

Never optically active rare earth complexes have made possible a catalytic asymmetric nitroaldol reaction far the first time. Structural elucidation reveals that the complexes consist of one rare earth metal, three lithium atoms, and three BINOL units. Applications of the catalytic asymmetric nitroaldol reaction to syntheses of several beta-blockers and erythro-AHPA have been also achieved. Although the lithium containing rare earth-BINOL complexes are not effective for Michael reactions, the optically active lanthanum-sodium-BINOL complex, prepared from La(O-i-Pr)(3), (R)-BINOL (3 mol equiv), and NaO-t-Bu (3 mol equiv), has been found to be quite effective as an asymmetric catalyst for various Michael reactions to give adducts in up to 92% ee. In addition, the optically active lanthanum-potassium-BINOL complex has been found to be useful for catalytic asymmetric hydrophosphonylation to imines.