Calcium Chloride (CaCl2) as Catalyst for Asymmetric Organic Reactions

Pybox–CaCl2 was found to be an efficient chiral catalyst for asymmetric 1,4-addition reactions of 1,3-dicarbonyl compounds with nitroalkenes, affording γ-nitro carbonyl compounds in high yields with high enantioselectivities. The reactions proceeded smoothly even in air, and were successfully applied to a continuous flow system.