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In order to effectively synthesize chiral ɑ-amino aldehydes,which have a wide range of potential applications in organic synthesis and medicinal chemistry,a highly chemo-and enantioselective hydrogenation of ɑ-formyl enamides has been developed.Along with our continuing research on asymmetric hydrogenation,an amido directing group and an electron-rich bisphosphine-Rh catalytic system have been utilized in this reaction.[1] Under different hydrogen pressures,the chiral ɑ-amido aldehydes and β-amido alcohols were obtained in high yields(97-99%)and with excellent chemo-and enantioselectivities(up to >99.9%ee).The hydrogenation can be carried out on a gram scale and under a high substrate/catalyst ratio(up to 20000 S/C),and the hydrogenated products were further converted to several important chiral products.Computations of the catalytic cycle gave a clear description for the R/S-pathways,provided a reasonable explanation for enantioselectivity,and revealed several other specific features.[2]