title: Unsymmetrical ferrocenylethylamine-derived monophosphoramidites: highly efficient chiral ligands for Rh-catalyzed enantioselective hydrogenation of enamides and alpha-dehydroamino acid derivatives.
abstract: [reaction: see text] A new family of unsymmetrical ferrocenylethylamine-derived monophosphoramidites were synthesized and successfully applied in the Rh-catalyzed enantioselective hydrogenation of a range of enamides and alpha-dehydroamino acid esters, and ee values of up to 99.5% were obtained for both types of substrate. These results suggest that unsymmetrical amine-derived monophosphoramidites can also exhibit excellent enantioselectivity for a broad range of substrates, comparable to or higher than those of the most efficient symmetrical amine-derived monophosphoramidites reported thus far.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
authors.forename: Qing-Heng
authors.initials: QH
authors.lastname: Zeng
authors.forename: Xiang-Ping
authors.initials: XP
authors.lastname: Hu
authors.forename: Zheng-Chao
authors.initials: ZC
authors.lastname: Duan
authors.forename: Xin-Miao
authors.initials: XM
authors.lastname: Liang
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Zheng