Bilitrienones from the chemical oxidation of dodecasubstituted porphyrins.
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.
Ongayi
Owendi
O
Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
Vicente
M Graça H
MG
Ghosh
Brahma
B
Fronczek
Frank R
FR
Smith
Kevin M
KM