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A new class of unsymmetrical hybrid phosphine-aminophosphine ligands has been prepared from commercially available, inexpensive (S)-1-phenylethylamine through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and displayed good enantioselectivities in the Rh-catalyzed asymmetric hydrogenation of various dimethyl α-benzoyloxyethenephosphonates bearing β-aryl, β-alkyl, and β-alkoxy substituents and N-benzyloxycarbonyl α-enamido phosphonates, in which up to 97% ee was obtained. A side-by-side comparison study disclosed that these new phosphine-aminophosphine ligands showed better enantioselectivity than BoPhoz ligands. [ABSTRACT FROM AUTHOR]