p-TsOH catalyzed Diels-Alder reaction of 3-(indol-3-yl)maleimides with 3-phenacylideneoxindoles in toluene at 80℃for two hours afforded cis/trans isomers of 3 a’,4’,6’,10 c’-tetrahydrospiro[indoline-3,5’-pyrrolo...p-TsOH catalyzed Diels-Alder reaction of 3-(indol-3-yl)maleimides with 3-phenacylideneoxindoles in toluene at 80℃for two hours afforded cis/trans isomers of 3 a’,4’,6’,10 c’-tetrahydrospiro[indoline-3,5’-pyrrolo[3,4-c]carbazoles]in nearly comparable yields,which could be easily converted to the corresponding 4’,6’-dihydrospiro[indoline-3,5’-pyrrolo[3,4-c]carbazole]in high yields and with high diastereoselectivity by further DDQ oxidation.Additionally,the similar reaction of 3-(indol-3-yl)maleimides with 2-arylidene-1,3-indanediones in toluene 80℃and sequential DDQ oxidation afforded functionalized dihydrospiro[indene-2,5’-pyrrolo[3,4-c]carbazoles]as major products.展开更多
基金financially supported by the National Natural Science Foundation of China(No.21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China。
文摘p-TsOH catalyzed Diels-Alder reaction of 3-(indol-3-yl)maleimides with 3-phenacylideneoxindoles in toluene at 80℃for two hours afforded cis/trans isomers of 3 a’,4’,6’,10 c’-tetrahydrospiro[indoline-3,5’-pyrrolo[3,4-c]carbazoles]in nearly comparable yields,which could be easily converted to the corresponding 4’,6’-dihydrospiro[indoline-3,5’-pyrrolo[3,4-c]carbazole]in high yields and with high diastereoselectivity by further DDQ oxidation.Additionally,the similar reaction of 3-(indol-3-yl)maleimides with 2-arylidene-1,3-indanediones in toluene 80℃and sequential DDQ oxidation afforded functionalized dihydrospiro[indene-2,5’-pyrrolo[3,4-c]carbazoles]as major products.