Recent trends in the synthesis of carbazoles: an update

The carbazole nucleus is a predominant feature of a vast array of heterocyclic compounds. It occurs in naturally occurring alkaloids, optoelectronic materials, and anion-binding ligands. Due to their various applications, there have appeared a plethora of synthetic methods for the construction of carbazoles. In this update, we focus on the recent developments and studies related to the synthesis of carbazoles spanning the period 2008-2011. Particular emphasis is placed on the methods involving cycloadditions and transition metal-assisted intramolecular aminations. (C) 2012 Elsevier Ltd. All rights reserved.