Study On Base-promoted Reactions Of EBXs With ?-bromoamides

Recently,the EBXs??³-iodines?are widely used as an electrophilic reagent in organic synthesis.In the first part of this dissertation,the various applications of EBXs reagents reported in recent years are reviewed,such as alkynylation,cyclization,and addition reactions.The synthesis and applications of new EBXs reagents and Vinylbenziodoxolones?VBXs?reagents from EBXs were explored in this dissertation.In the second part,a[3+2]-cycloaddition reaction between EBXs and azaoxyallyl cations to afford a spirocyclic?³-iodines bearing a 4-oxazolidinone ring in 66-98%yields,has been devoloped.The reaction conditions were optimized and the substrate scope was explored.Furthermore,the compound 3ab was structurally characterized by X-ray analysis,and the mechanism was speculated.In the third part,a copper?I?-catalyzed the spirocyclic?³-iodines was transformed to both 4,1-benzoxazepine-2,5-dione derivatives in 90-93%yields and 1,3-diyne derivatives in 90-99%yields.The reaction conditions were optimized and the substrate scope was explored.Furthermore,the compound 2a was structurally characterized by X-ray analysis,and the mechanism was speculated.In the fourth part,the additional reaction between EBXs and?-bromoamide under the reaction conditions of TMG as base and DCE as solvent,which provide a new vinylbenziodoxolones?VBXs?derivatives in 90-96%yields,has been developed.The reaction conditions were optimized and the substrate scope was explored.The compound 2a was structurally characterized by X-ray analysis.In the fifth part,using TMG as base and CH₃CN as solvent,the new VBXs was easily tansformed to oxime ethers in excellent yields.The reaction conditions were optimized and the substrate scope was explored.Moreover,the relative configuration of compounds 2f was structurally characterized by X-ray analysis and the possible mechanism was speculated.A new method to construct oxime ethers derivatives has been developed.