title: Bilitrienones from the chemical oxidation of dodecasubstituted porphyrins.
abstract: The structure of the ring-opened product from direct oxidation of meso-tetraarylporphyrins has been controversial for three decades. Herein we show that bilitrienones 2 are obtained from oxidation of metal-free dodecasubstituted porphyrins 1 in the presence of sodium nitrite, trifluoroacetic acid and air oxygen. The presence of the para-nonyl groups in 1b stabilized the corresponding bilitrienone 2b, which was characterized by X-ray crystallography. In the absence of the para-nonyl groups bilitrienone 2a undergoes a rapid hydration reaction, giving biladienone 3a as the major isolated product. The molecular structures of 2b and 3a, and. the photochemical isomerization of 3a are discussed.
authors.affiliation: Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Owendi
authors.initials: O
authors.lastname: Ongayi
authors.forename: M Graça H
authors.initials: MG
authors.lastname: Vicente
authors.forename: Brahma
authors.initials: B
authors.lastname: Ghosh
authors.forename: Frank R
authors.initials: FR
authors.lastname: Fronczek
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Smith