Copper-Catalyzed ?-C(sp~3)–H Functionalization Of Oxime Esters

This thesis deals with the cyclization and acyloxy migration reactions of O-acyl ketone oximes under copper-mediated visible light photocatalysis.It consists of three parts:In the first chapter,recent avdances in applying of intramolecular hydrogen atom transfer?HAT?to hereocycle preparation and C?sp³?–H functionalization are brief reviewed,with an emphasis on those involving nitrogen-centered radicals?Hofmann–L?ffler–Freytag?HLF?reaction?.The second and third chapters introduce the research work during the period of my graduate study.The main results include:?1?The cyclization of O-pentafluorobenzoyl ketone oximes was investigated under the condition of visible light photoredox catalysis.By using cuprous complex[Cu?DPEphos??bcp?]PF₆ as catalyst,a variety of O-pentafluorobenzoyl ketone oximes can be converted to 2,3-dihydropyrrole compounds in moderate to good yields via HLF cyclization via intermediacy of iminyl radicals.?2?The acyloxy migration of O-pentafluorobenzoyl ketone oximes was preliminarily investigated.It was found that blue light irradiation of 1,4-diphenylbutan-1-one O-perfluorobenzoyl oxime in the presence of catalytic amount of[Cu?dap?₂]⁺in dichloroethane resulted in the formation of pentafluorobenzoyloxy migration product4-oxo-1,4-diphenylbutyl 2,3,4,5,6-pentafluorobenzoate.Lewis acids such as InCl₃ are beneficial to the reaction.The reaction also took place at elevated temperature by using FeBr₂ and FeCl₃ as catalyst.This is a new discovery and has potential synthetic application value,such compounds can be used as substrates for ketone compounds to synthesize new drug molecules and organic materials.