Reaction of 2-chloro-1-azaazulene with diphenylcyclopropenone;: Dimerization of the cycloadduct attended by cine-substitution and rearrangement

2-Chloro-1-azaazulene reacted with diphenylcyclopropenone to give 3,4-diphenyl-2a,5-dihydro-2H-2a-azabenz[cd]azulene-2,5-dione and 6-[(3,4-diphenyl-5-oxo-2a,5-dihydro-2H-2a-azabenz[cd]azulen-2-ylidene)-methyl]-3,4-diphenyl-2a,5-dihydro-2a-azaacenaphtylen-5-one; the latter would be produced via cycloaddition and at successive cine-substitution followed by rearrangement.