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-Stuttgart. - 2015. - Vol. 47, № 22. - С. 3561-3572. - Bibliogr. : p. 3572 (11 ref) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): 5,11-DIHYDROINDOLO[3,2-B]CARBAZOLES -- 2-ARYLGLY-OXALS -- ACYLATION 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. |