Synthesis of 1- and 2-(2-quinolyl)azulenes by the Friedlaender reaction of acetylazulenes

Article abstract of DOI:10.1002/jhet.5570330350

1-Acetylazulene and 3-methyl-, 3-ethyl-, and 3-propyl-substituted 1-acetylazulenes were prepared by the reaction of 3-acetyl-2H-cyclohepta[b]furan-2-one with in situ generated enamines from aldehydes and amines. These four 1-acetylazulenes reacted with 2-aminobenzaldehyde and its 4,5-dimethoxy- and 4,5-methylenedioxy-substituted derivatives in the presence of sodium ethoxide to afford twelve 1-(2-quinolyl)azulenes. In a similar manner, three 2-(2-quinolyl)azulenes were also prepared from 2-acetylazulene.