Asymmetric [3 + 2] Cycloaddition Reaction Of Diazo Phosphonates With ?,?-Unsaturated Pyrazolinone

Pyrazolinone is an important class of organic compounds.There are four substitutable sites on the azole ring,and different substitution sites and substituents endow the pyrazole compounds have significant differences biological activities.Therefore,the synthesis of various optically active pyrazolones or pyrazoline derivatives is of great significance.The research and development of pyrazole derivatives has become a hot topic in the fields of pesticides,medicine,biology and materials.In this thesis,under the catalysis of Zn(II)/BOX complex,the asymmetric[3+2]cycloaddition reaction of diazophosphonate with?,?-unsaturated pyrazolone was achieved,and a series of potential bioactive pyrazoline-phosphonate spiro compounds were obtained.Through the investigation of the influence of the catalyst,the amount of catalyst,the type of base,the amount of base,solvent,temperature and other conditions on the reaction,the best conditions for the reaction were determined:10mol%Zn(OTf)2 as Lewis acid,11 mol%Compound 171 as a ligand,15 mol%DABCO as a base,DCM as the solvent,at 0 ~oC,the reaction gave chiral pyrazoline-phosphonate spiro compounds with up to 96%yield,93%enantioselectivity and 84:16 diastereoselective.