Synthesis of chiral piperazin-2-ones through palladium-catalyzed asymmetric hydrogenation of pyrazin-2-ols

A palladium-catalyzed asymmetric hydrogenation of pyrazines containing a tautomeric hydroxyl group has been developed, providing a facile access to chiral disubstituted piperazin-2-ones with excellent diastereoselectivities and enantioselectivities. The product could be conveniently converted into chiral piperazines without loss of optical purity.