Chiral 1,2,3,4‐Tetrahydro‐1‐naphthylamine‐Derived Phosphine‐Phosphoramidite Ligand (THNAPhos): Application in Highly Enantioselective Hydrogenations of Functionalized CC Bonds

We have recently reported a new chiral 1,2,3,4‐tetrahydro‐1‐naphthylamine‐derived phosphine‐phosphoramidite ligand, (R_c,R_a)‐THNAPhos, that is highly efficient in the rhodium‐catalyzed asymmetric hydrogenation of a broad range of α‐enol ester phosphonates. To further demonstrate the utility of THNAPhos in asymmetric hydrogenation, in this paper, we describe its new application in the asymmetric hydrogenation of α‐dehydroamino acid esters, enamides, dimethyl itaconate and α‐enamido phosphonates. The results disclosed that the Rh/(R_c,R_a)‐THNAPhos complex is highly effective for the enantioselective hydrogenation of these kinds of functionalized CC olefins, affording the corresponding hydrogenation product in excellent enantioselectivities (normally over 99% ee).