Gold‐Catalyzed Intramolecular Alkyne Cycloisomerization Cascade: Direct Synthesis of Aryl‐Annulated[a]carbazoles from Aniline‐Substituted Diethynylarenes

Aniline‐substituted diethynylarenes, which are readily synthesized through Sonogashira coupling reactions from commercially available 1,2‐dihaloarenes, directly produce aryl‐ and heteroaryl‐annulated[ a ]carbazoles by the gold‐catalyzed intramolecular cascade hydroamination/cycloisomerization without producing theoretical by‐products. This new atom‐economical route is easily applicable to various aryl‐annulated[ a ]carbazoles containing an alkyl, aryl or ester substituent.