Recent development of Brensted acid-promoted synthesis of quinoline, isoquinoline and carboline derivatives

Department of Chemistry, University of Kalyani, Kalyani-741 235, West Bengal, India E-mail :kcm@klyuniv.ac.in Fax : 91-33-25828282 Manuscript received 04 March 2013, accepted 07 March 2013 Various quinolines, isoquinolines and carbolines-based natural and unnatural products can be synthesized by Bronsted acid-promoted cyclization. We have made an attempt to summarize the progress made in this area during the period 2005 to date. This article describes the synthetic routes to these heterocycles that involve a Bronsted acid-promoted cyclization as a crucial step or a Bronsted acid as a co-catalysts with other transition metals