and 5. Electrophilicsubstitutionreactions are a very important and general methodology for the functionalization of aromatic compounds. In azulene derivatives, there are numerous reports for the electrophilicsubstitutionreactions at the 1and 3-positions of the azulene ring. However, there are few reports on the functionalization of azulene derivatives at the 2-position utilizing electrophilic substitution
high yields into 1-azulenyl methyl and phenyl sulfides and 1,3-bis(methyl- and phenylthio)azulenes through treatment with diethylamine is also described. Reaction of the 1-azulenylsulfides with MCPBA afforded 1-azulenyl sulfoxides, which were then efficiently transformed into 1,1′-biazulene derivatives under acidic conditions. The redox properties of 1-azulenyl methyl and phenyl sulfides, 1,3-bis(methyl-