Mono- versus bidentate ligands in rhodium-catalyzed asymmetric hydrogenation. A comparative rate study.


[reaction: see text] Bidentate chiral phosphines are no longer essential for achieving a fast and highly enantioselective hydrogenation of alpha- or beta-dehydroamino acid derivatives. In particular, a readily accessible and stable monodentate phosphoramidite can be highly effective in these asymmetric hydrogenations.