Facile synthesis of fused polycyclic compounds via intramolecular oxidative cyclization/aromatization of β-tetralone or β-tetralone oximesElectronic supplementary information (ESI) available. CCDC 1822084 and 1856722. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8ob02031k

A mild and efficient NBS promoted intramolecular oxidative cyclization/aromatization of β-tetralone oximes has been explored. Under the optimized conditions, fused α-carbolines containing pentacyclic rings were obtained in moderate to good yields. Furthermore, various benzo[5,6]chromeno[2,3- b ]indoles were successfully synthesized in moderate yields from β-tetralones using slightly modified conditions. We proposed a possible reaction pathway based on the experimental results. A mild and efficient NXS promoted intramolecular oxidative cyclization/aromatization of β-tetralone or β-tetralone oximes has been explored.