Pd(OAc)2-catalyzed acetoxylations of 3-aryl or 3-alkyl groups mounted on a 2-isoxazoline ring were studied. Ortho-selective C–H bond activation directed by an isoxazolinyl group was realized. 2-Isoxazoline rings without and with one or two alkyl substituents in the 5-position were effective directing groups. The substituent effect on reactivity and regioselectivity was examined. The acetoxylation was applied to the synthesis of useful intermediates.

The weak acid has been identified as an efficient basicity-mask to overcome the basicity barrier imparted by aliphatic amines in the Pd-catalyzed hydroaminocarbonylation, which enables both aromatic and aliphatic amines to be applicable in the palladium-catalyzed hydroaminocarbonylation reaction. Notably, by using this protocol, the marketed herbicide of Propanil and drug of Fentanyl could be easily obtained in a one-pot manner.

The regioselectivity of the o-semidine, p-semidine, and diphenyline rearrangements of unsymmetrical N,N′-diarylhydrazines was studied experimentally. The results indicate that their electron-rich nitrogen atom is first protonated and then the electron-poor non-protonated nitrogen atom undergoes an N[1,3]-sigmatropic shift to the ortho-position of the electron-rich aryl rings, generating key intermediates. The intermediates can undergo (1) a direct proton transfer to give o-semidines, (2) a second N[1,3]-shift of the electron-poor nitrogen atom and then proton transfer to furnish p-semidines, and (3) a [3,3]-sigmatropic shift and subsequent proton transfer to yield diphenylines. It is the first N[1,3]-sigmatropic shift step that plays an important role in controlling the regioselectivity in the three rearrangements, further determining the structures of o-semidines, p-semidines, and diphenylines. The current results provide new insights into the o/p-semidine and diphenyline rearrangements and useful information for controlling and predicting the structures of the rearrangement products.

1,3-Dipolar cycloadditions of triisopropylsilyl nitronates and 2-alkylacroleins produced isoxazolines bearing a chiral quaternary center in high yields and enantioselectivities with the aid of a chiral oxazaborolidine catalyst. One chiral isoxazoline product was converted to (R)-(+)-Tanikolide in 9 steps in a total yield of 43%.

Cu(OTf)2 and chiral BOX ligand-catalyzed 1,3-dipolar cycloadditions of triisopropylsilyl nitronates with α,β-unsaturated carboximides produced chiral isoxazolines in high yields, high enantioselectivities, and complete diastereoselectivities. These chiral isoxazoline products were further converted into structurally diversified derivatives, which demonstrated the utility of the new method of constructing isoxazolines. The transition-state structure of cycloaddition was proposed in the light of the relative and absolute configurations of the products.

A catalytic asymmetric Diels–Alder reaction of an aryl vinyl ketone with 1,3-dienylcarbamate has been developed. Cyclohexenes bearing vicinal amino and aroyl groups in a cis-configuration were prepared in excellent ee (>99%) and endo (single diastereomer) selectivity. The absolute configuration of one DA product was unambiguously confirmed using XRD analysis. The transition state structure was proposed on the basis of DFT calculations.

A catalytic asymmetric Diels–Alder reaction of an aryl vinyl ketone with 1,3-dienylcarbamate has been developed. Cyclohexenes bearing vicinal amino and aroyl groups in a cis-configuration were prepared in excellent ee (>99%) and endo (single diastereomer) selectivity. The absolute configuration of one DA product was unambiguously confirmed using XRD analysis. The transition state structure was proposed on the basis of DFT calculations.