Highly efficient and enantioselective synthesis of chiral lactones via Ir-catalysed asymmetric hydrogenation of ketoesters.

Owing to the biological significance and great synthetic value of chiral lactones and their derivatives, increasing attention has been paid to developing effective synthetic methods for chiral lactones. We herein report an efficient asymmetric hydrogenation of benzo-fused ketoesters, γ-ketoesters and biaryl-bridged ketoesters catalyzed by chiral iridium complexes bearing ferrocene-based chiral ligands, furnishing a series of chiral lactones in superb yields and excellent enantioselectivities (up to 99% yields and up to 99% ee).