Synthesis and reactivity of tetraphenylazuliporphyrins derived from 6-tert-butyl and 6-phenylazulene

ORGN 169

Jessica A. El-Beck, jaelbec@ilstu.edu and Timothy D. Lash, tdlash@ilstu.edu. Department of Chemistry, Illinois State University, Normal, IL 61790-4160

Porphyrins analogues with carbocyclic rings in place of one of more of the usual pyrrole units are attracting considerable interest due to their unusual spectroscopic and chemical properties. Azuliporphyrins are carbaporphyrinoid systems incorporating an azulene subunit. These macrocycles are poorly soluble in organic solvents but show interesting chemistry, including the ability to form nucleophilic adducts. This property is believed to be responsible for the oxidative rearrangement of azuliporphyrins under alkaline conditions to afford benzocarbaporphyrins. In order to improve the solubility characteristics of these compounds and to modify the reactivity at the seven-membered rings, azuliporphyrins have been synthesized from 6- tert-butyl and 6-phenylazulene. The substituted azulene, pyrrole and benzaldehyde were reacted in the presence of BF3 to give the meso-subtituted azuliporphyrins. Preliminary results indicate that these substituents do not prevent oxidative rearrangements from occurring.