34085-07-9Relevant academic research and scientific papers
meso-Reactivity of Porphyrins and Related Compounds. Part 9. Photo-oxygenation of Octaethyloxophlorin
Bonnett, Raymond,Chaney, Brian D.
, p. 1063 - 1068 (2007/10/02)
The photo-oxygenation of octaethyloxophlorin has been investigated under basic and under neutral conditions.In both cases unstable intermediate stages are observed spectroscopically.In methanolic sodium methoxide the solution becomes bleached and tetraethyl(methanol)propentdyopent is a significant product.In neutral solutions (e.g. benzene-methanol) the major products are octaethyl-5,15-dioxo-5,15-dihydroporphyrin (4) and octaethyl-19-formyl-21H,24H-bilin-1,15-dione (7), the formation of octaethyl-21H,24H-bilin-1,19-dione (6) being a minor pathway.A mechanistic rationalisation is proposed.
ON THE ROLE OF SINGLET OXIGEN IN THE SELF-SENSITIZED PHOTO-OXYGENATION OF BILIRUBIN AND ITS PYRROMETHENONE MODELS
Landen, G. L.,Park, Y. -T.,Lightner, D. A.
, p. 1893 - 1908 (2007/10/02)
4-Ethyl-3-methyl-5-(4-ethyl-3,5-dimethylpyrrolyl-2-methylidene)-3-pyrrolin-2-one (1), 3,4-diethyl-5-(4-ethyl-3,5-dimethylpyrrolyl-2-methylidene)-3-pyrrolin-2-one (2) and xanthobilirubinic acid (XBR) undergo self-sensitized photo-oxygenation, as does bilirubin.The reaction products of 1 consist of methylethylmaleimide, kryptopyrrole aldehyde and its photo-oxygenation product and oxygenated dipyrroles.The same products are formed from 2, except xeronimide is found instead of methylethylmaleimide.Kinetic studies indicate that singlet oxygen is not necessarily involved in the photo-oxygenation reactions.Geometric photoisomerization (ZE) of 1 and 2, and XBR proceeds at an even faster rate than photosensitized oxygenation.
