Catalytic asymmetric Mannich reactions of imines with weakly acidic simple amides were developed using a chiral potassium hexamethyldisilazide (KHMDS)−bis(oxazoline) potassium salt (K-Box) catalyst system. The desired reactions proceeded to afford the target compounds in high yields with high diastereo-and enantioselectivities. It was suggested that a K enolate interacted with K-Box to form a chiral K enolate that reacted with imines efficiently. In this system, K-Box (potassium salt of Box) worked as a chiral ligand of the active potassium species.

Asymmetric epoxidation reactions of chalcone derivatives catalyzed by chiral calcium complexes using hydrogen peroxide were developed. The epoxidation reactions proceeded smoothly to afford the desired products in good yields with good enantioselectivities. This is the first example of chiral calcium-catalyzed asymmetric epoxidation reactions using hydrogen peroxide as the terminal oxidant.