Study On Synthesis And Derivatization Of Spirooxindoles

This thesis mainly consists of four parts:review of[3+2]dipolar cycloaddition reaction of arynes,study on the[3+2]dipolar cycloaddition of arynes with3-diazoindolin-2-ones,study on the construction of 6H-benzofuro[2,3-b]indoles and5,6-dihydroindolo[2,3-b]indoles via UV light-mediated diradical cyclization,and the construction of CF₃-containing spiro-epoxyoxindoles via Corey-Chaykovsky reaction Chapter 1:Review of the[3+2]dipolar cycloaddition reaction of arynesThe background of arynes was introduced,including preparation,structure and chemical property,and the[3+2]dipolar cycloaddition reaction about arynes was summarized at the same time.Chapter 2:Study on the[3+2]dipolar cycloaddition of arynes with3-diazoindolin-2-onesIn this chapter,an efficient protocol for facile construction of spro[indazole-3,3'-indolin]-2'-ones was developed via[3+2]dipolar cycloaddition of arynes with 3-diazoindolin-2-ones under mild conditions in excellent yields.Subsequent thermal isomerization or acidic isomerization of the products afforded readily indazolo[2,3-c]quinazolin-6?5H?-ones.Chapter 3:Study on the construction of 6H-benzofuro[2,3-b]indoles and5,6-dihydroindolo[2,3-b]indoles via UV light-mediated diradical cyclizationInthischapter,aunifiedprotocolfortheconstructionof6H-benzofuro[2,3-b]indoles and 5,6-dihydroindolo[2,3-b]indoles via UV light-mediated diradical cyclization was developed and preliminary efforts were also made to functionalize at C3 position of 6H-benzofuro[2,3-b]indoles.Chapter 4:Study on the construction of CF3-containing spiro-epoxyoxindoles via Corey-Chaykovsky reactionIn this chapter,CF₃-containing spiro-epoxyoxindoles were successfully prepared via Corey-Chaykovsky reaction of N-alkyl isatins with the ylide generated from Ph₂S⁺CH₂CF₃OTf^-with almost exclusive diastereoselectivity.Further derivatization of these spiro-epoxyoxindoles was explored via photochemical reaction or Lewis acid-promoted allylation.