R 35 Regioselective C2- and C8-Acylation of 5,11-Dihydroindolo[3,2-b]carbazoles and the Synthesis of Their 2,8-Bis(quinoxalinyl) Derivatives [Electronic resource] / R. A. Irgashev, N. A. Kazin, G. A. Kim, G. L. Rusinov, V. N. Charushin // Synthesis (Germany). - 2015. - Vol.47, № 22. - С. 3561-3572. - Bibliogr. : p. Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ACYLATION -- TYPE HETEROACENES -- QUINOXALINES Аннотация: An efficient approach for the double acetylation of 5,11-dihexyl-6,12-di(hetero)aryl-substituted 5,11-dihydroindolo[3,2-b]carbazoles with acetic anhydride in the presence of boron trifluoride etherate has been developed, thus affording the corresponding 2,8-diacetyl derivatives in good yields. A similar acylation has been shown to occur by the reaction of anhydrides of other carboxylic acids. Oxidation of the obtained 2,8-diacetyl derivatives with selenium dioxide takes place on heating or under microwave irradiation, thus resulting in the formation of the corresponding 2,8-diglyoxals. The latter proved to react with aromatic o-diamines to afford new indolo[3,2-b]carbazoles bearing quinoxalinyl fragments at C-2 and C-8. Major optical properties of quinoxaline-containing indolo[3,2-b]carbazoles have been measured. |