Formal [4 + 2] benzannulation of 2-alkenyl indoles with aldehydes: a route to structurally diverse carbazoles and bis-carbazoles

• Published in: Organic & biomolecular chemistry Vol. 17; no. 7; pp. 1822 - 1826
• Main Authors: Banerjee, Ankush, Guin, Avishek, Saha, Shuvendu, Mondal, Anushree, Maji, Modhu Sudan
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 13.02.2019
• Subjects: Aldehydes; Carbazoles; Catalysts; Functional groups; Indoles; NMR; Nuclear magnetic resonance; Oxygen; Reagents

Construction of structurally diverse carbazoles and bis-carbazoles by protecting-group-free formal [4 + 2]-benzannulation of 2-alkenyl indoles and aldehydes is demonstrated. The sequence of four different reactions is executed in one-pot using readily available and cheap bottle reagents as catalysts...