Some reactions of 3-phenyl-8-triphenylphosphoimino-1-azaazulene

Reaction of 3-phenyl-8-triphenylphosphoimino-1-azaazulene (1) with arylaldehyde gave 2-aryl-4-phenyl-3H-1,2a-diazacyclopent[cd]azulenes. Reaction of I with trans-cinnamaldehyde gave 3-benzyl-1-pheny-2a,5-diazabenz[cd]azulene as cyclization product. Cycloaddition reaction of 1 with dimethyl acetylenedicarboxylate gave tetramethyl 4-phenyl-9,9b-diazaindeno[4,3a,3,2-bcd]azulene-1,2,3,9a-tetracarboxylate and hexamethyl 6phenyl-3aH-10c-azaacephenanthryene-1,2,3,3a,4,5-hexacarboxylate.