Relay Catalysis of Bismuth Trichloride and Byproduct Hydrogen Bromide Enables the Synthesis of Carbazole and Benzo[α]carbazoles from Indoles and α-Bromoacetaldehyde Acetals
using bismuth trichloride as a catalyst. The reaction was triggered by a bismuth trichloride‐catalyzed Friedel‐Crafts alkylation of these two precursors, which provided a tryptaldehyde intermediate that underwent intramolecular olefination to form the final product. Interestingly, the HBr byproduct generated in the upstream step of the reaction catalyzed the following downstream reaction steps, thus
Cascade annulative π-extension for the rapid construction of carbazole based polyaromatic hydrocarbons
作者:Samrat Kundu、Ankush Banerjee、Shyam Chand Pal、Meghna Ghosh、Modhu Sudan Maji
DOI:10.1039/d1cc00668a
日期:——
Brønsted acid catalyzed cascade benzannulation strategy for the concise synthesis of benzo[a]carbazoles is reported. Efficacy of the methodology was further validated by synthesizing structurally diverse, extensive π-conjugated carbazole based PAHs.