A 10 A convenient synthesis of new 5,11-dihydroindolo[3,2-b]carbazoles bearing thiophene, 2,2′-bithiophene or 2,2′:5′,2″-terthiophene units at C-2 and C-8 positions / R. A. Irgashev, N. A. Kazin, G. L. Rusinov, V. N. Charushin // Tetrahedron Letters. - 2017. - Vol. 58, № 32. - P3139-3142 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): 5,11-DIHYDROINDOLO[3,2-B]CARBAZOLE -- THIOPHENE -- 3-CHLOROACRYLALDEHYDE -- THE VILSMEIER–HAACK FORMYLATION -- THE FIESSELMANN REACTION Аннотация: A series of new 5,11-dihydroindolo[3,2-b]carbazole derivatives, containing functional thiophene, 2,2′-bithiophene or 2,2′:5′,2″-terthiophene moieties at both C-2 and C-8 positions of their fused scaffolds, have been obtained from 2,8-diacetyl-substituted 5,11-dihydroindolo[3,2-b]carbazole compounds through the effective strategy, which is based on the sequence of two reactions, namely the Vilsmeier–Haack formylation and the Fiesselmann thiophene synthesis. The starting acetyl substituted materials have been transformed into the corresponding 3-chlorocrylaldehyde-containing compounds by treatment with POCl3-DMF complex, followed by the reaction with alkyl thioglycolates or α-mercaptoacetone in the presence of triethylamine to afford 2-carboalkoxythiophene- or 2-acetylthiophene-linked derivatives. 2-Acetylthiophene derivatives have further been involved into the same sequence of reactions to obtain 2,2′-bithiophene-, and 2,2′:5′,2″-terthiophene-linked 5,11-dihydroindolo[3,2-b]carbazole compounds. \\\\Expert2\\NBO\\Tetrahedron Letters\\2017 v.58 p.3139-3142.pdf |