Generation and rearragement of 4aH-carbazoles
Abstract
Thermal and photochemical decomposition of benzotriazoles (3) gives carbazoles (4) and (5), and cyclopentaquinolines (6), the formation of these products being rationalised by rearrangements in 4aH-carbazole intermediates (7); one proposed intermediate (11c) has been intercepted in an extended cycloaddition reaction with acrylonitrile.