[4+2] Annulation of 3-(2,2-diethoxyethyl)-1,3-dicarbonyl compounds with indoles catalyzed by Brønsted acid ionic liquid for the synthesis of carbazoles
作者:Yuying Du、Wenyu Xue、Ruoxuan Gao、Yanlong Gu、Limin Han
DOI:10.1016/j.tetlet.2018.10.029
日期:2018.11
Various carbazoles were synthesized via [4+2] annulation of 3-(2,2-diethoxyethyl)-1,3-dicarbonyl compounds with indoles. A Brønsted acid ionic liquid, [BPy]HSO4, was proven to be effective catalyst for this reaction. The ionic liquid catalyst can be recycled three times without significant loss of its catalytic activity.
implication of carbazole scaffolds in medicinal chemistry, photoelectronic materials and chromophores, the molecules containing the carbazole motif have attracted significant attention over the years. In this work, the vibronic contributions to carbazole structures could facilely change the solvatochromic effect, absorption wavelength, emission wavelength, and Stokes shifts of six 2-carbonyl carbazole ketones