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The synthesis and characterization of a new series of aryl-and cycloalkyl-substituted aminophosphine phosphinites (1-8) obtained from the reaction of the three precursors (S)-2-hydroxymethyl azetidine, (S)-3-hydroxymethyl-1,2,3,4-tetrahydroisoquinoline, and (S)-2hydroxymethylindoline and chlorophosphines is described. The aromatic ring in (S)-2hydroxymethylindoline has allowed the synthesis and isolation of tricarbonyl chromium complexed amino alcohols syn-10 and anti-10, which were similarly converted into the corresponding aminophosphine phosphinites 11-13, presenting a stereogenic center and a planar chirality. Ligand 5 ((S)-Cp,Cp-IndoNOP) revealed an unprecedented 31 P NMR fluxional behavior related to a rotation inhibition around the P-heteroatom (N and O) bonds. These new AMPP ligands were used in the enantioselective hydrogenation of various R-functionalized ketones, i.e., dihydro-4,4-dimethyl-2,3-furandione 14, N-benzyl benzoylformamide 15, ethylpyruvate 16, and 2-(N,N-dimethyl)aminoacetophenone hydrochloride 17. The stereoelectronic effects generated by the presence of the tricarbonyl chromium moiety onto the hydrogenations have been assessed. The beneficial effect of the matching chiralities in ligand syn-12 associated with the use of the most appropriate nonchiral ligand Cl has resulted in a win of 13% of ee for the rhodium-based hydrogenation of 15. While using the most suitable new chiral AMPP ligand from this study, the four above-mentioned substrates were converted into the corresponding optically active alcohols in >99% ee (l4/5), >99% ee (15/6), 87% ee (16/5), and >99% ee (17/5), respectively.

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