Efficient access to chiral dihydrobenzoxazinones via Rh-catalyzed hydrogenation†
Abstract
Rh/(S)-DTBM-SegPhos-catalyzed asymmetric hydrogenation of prochiral (Z)-2-(2-oxo-2H-benzo[b][1,4]oxazin-3(4H)-ylidene)acetate esters was successfully developed. A series of chiral dihydrobenzoxazinones were prepared through this efficient methodology with good to excellent results (up to >99% conversion, 93% yield and >99% ee), which are important motifs in the biologically active molecules.