Cheap transition metal Ni-catalyzed asymmetric hydrogenation of 2-oxazolones was successfully developed, which provided an efficient synthetic strategy to prepare various chiral 2-oxazolidinones with 95%–99% yields and 97%−>99% ee. The gram-scale hydrogenation could be proceeded well with >99% ee in the presence of low catalyst loading (up to 3350 TON). This Ni-catalyzed hydrogenation protocol demonstrated great synthetic utility, and the chiral 2-oxazolidinone product was easily converted to a variety of other important molecules in good yields and without loss of ee values, such as chiral dihydrothiophene-2­(3H)-thione, amino alcohol, oxazoline ligand, and allenamide. Moreover, a series of deuterium labeling experiments, control experiments, and DFT calculations were conducted to illustrate a reasonable catalytic mechanism for this Ni-catalyzed asymmetric hydrogenation, which involved a tautomerization between the enamine and its isomer imine and then went through asymmetric 1,2-addition of Ni­(II)-H to the preferred imine.

Ir-catalyzed asymmetric hydrogenation of quinolines was developed, and both enantiomers of chiral tetrahydroquinoline derivatives could be easily obtained, respectively, in high yields with good enantioselectivities through the adjustment of reaction solvents (toluene/dioxane: up to 99% yield, 98% ee (R), TON = 680; EtOH: up to 99% yield, 94% ee (S), TON = 1680). It provided an efficient and simple synthetic strategy for the enantiodivergent synthesis of chiral tetrahydroquinolines, and gram-scale asymmetric hydrogenation proceeded well with low-catalyst loading in these two reaction systems. A series of deuterium-labeling experiments, control experiments, and 1H NMR and electrospray ionization-mass spectrometry experiments have been conducted, and a reasonable and possible reaction process was revealed on the basis of these useful observations.

Rh-catalyzed highly chemo- and enantioselective hydrogenation of β-sulfonyl-α,β-unsaturated ketones was first successfully developed. Remarkably, a variety of enantioenriched γ-ketosulfones were generated in good to high yields with excellent chemo/enantioselectivities (82–99% yields, >99:1 chemoselectivity, 88 to >99% ee). Moreover, the gram-scale asymmetric hydrogenation was carried out smoothly in 97% yield and 97% ee. Preliminary DFT computations furnished a reasonable explanation for the high chemoselectivity and enantioselectivity.

Efficient Ni/(S,S)-Ph-BPE-catalyzed asymmetric hydrogenation of α-substituted α,β-unsaturated phosphine oxides/phosphonates/phosphoric acids has been successfully developed, and a wide range of chiral α-substituted phosphines hydrogenation products were obtained in generally high yields with excellent enantioselective control (92%–99% yields, 84%−>99% ee). This method features a cheap transition metal nickel catalytic system, high functional group tolerance, wide substrate scope generality, and excellent enantioselectivity. A plausible catalytic cycle was proposed for this asymmetric hydrogenation according to the results of deuterium-labeling experiments.