Studies On Stereoselective Cycloaddition Of N-acyliminium Cations With α,β-Unsaturated Ketones And Esters

This paper introduces generation and reaction of the N-acyliminium cations,and the application in organic synthesis,especially the cycloaddition reactions of N-acyliminium cations.The first part is the summary of N-acyliminium cations.The second part is the research of the reaction of N-acyliminium cations.(1) The stereoselective cycloaddition of N-acyliminium cations,produce from 3-hydroxy-2-phenylisoindolin-1-one,5-hydroxy-1-phenyl-1H-pyrrol-2(5H)-one or 5-hydroxy-1-phenylpyrrolidin-2-one in the presence of BF₃·Et₂O,withα,β-unsaturated ketones and esters.(2) The cycloaddition reaction of N-acyliminium cations,produce from 3-hydroxy-2-phenylisoindolin-1-one in the presence of BF₃·Et₂O,with imine.The cyclization reaction of 5-hydroxy-1-methyl-4-(2-phenyl-1H-indol-3-yl)-Pyrrolidin-2-one. The condensation reactions of active methylene compounds such as 1,3-dicarbonyls withω-hydroxylactam 2,3-dihydro-3-hydroxy-2-arylisoindol-1-one under the influence of Lewis acid.