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A new class of chiral ferrocenyl diphosphine ligands with an imidazole ring, (Rc,SFc)-ImiFerroPhos, has been prepared from acylferrocenes through a five-step transformation and successfully applied in the Rh-catalyzed asymmetric hydrogenation of various 3-aryl-substituted 2-phosphonomethylpropenoates, in which a series of chiral 3-phosphono-2-arylmethylpropanoic acid derivatives were achieved in ee values of up to 98%. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of optically active 1-aryl or 1-alkyl substituted ethyiphosphonates, based on the first Rh- catalyzed asymmetric hydrogenation of corresponding α,β-unsaturated precursors with a P-stereogenic BoPhoz-type ligand under the mild condition, was developed, in which a wide range of 1-aryl or 1-alkyl substituted ethyiphosphonates were achieved in up to 98% ee. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of chiral alkylphosphonates bearing a β-stereogenic center, based on the Rh-catalyzed asymmetric hydrogenation of corresponding β-substituted β,γ-unsaturated phosphonates with a ferrocenebased monophosphoramidite ligand under the mild hydrogenation conditions, was developed, in which an ee value of up to 98% was obtained. [ABSTRACT FROM AUTHOR]

A series of BoPhoz-type ligands were successfully applied in the rhodium-catalyzed asymmetric hydrogenation of a number of β-substituted or unsubstituted α-(phthalimidomethyl)acrylates, affording good to excellent enantioselectivities. The results suggested that the presence of an N-H proton in the BoPhoz backbone could significantly improve the enantioselectivity, and ligand (Sc,Rp)-1d, bearing two CF3-groups in the 3,5-position of the phenyl ring of aminophosphino moiety, showed the highest enantioselectivity. [ABSTRACT FROM AUTHOR]