## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v
Photoinduced molecular rearrangements. Some comments on the ring-photoisomerization of 1,2,4-oxadiazoles into 1,3,4-oxadiazoles
✍ Scribed by Silvestre Buscemi; Andrea Pace; Nicolò Vivona; Tullio Caronna
- Publisher
- Journal of Heterocyclic Chemistry
- Year
- 2001
- Tongue
- English
- Weight
- 34 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0022-152X
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The ring‐photoisomerization of 3‐amino‐ and 3‐methylamino‐5‐phenyl‐1,2,4‐oxadiazoles into the corresponding 2‐amino‐ and 2‐methylamino‐5‐phenyl‐1,3,4‐oxadiazoles has been reinvestigated by examining the effect of a base on the photoreaction. On irradiating at λ = 254 nm in methanol, yields of the ring‐photoisomers were found to be significantly enhanced by the addition of triethylamine (TEA) in the photoreaction medium. By contrast, irradiation of the 3‐amino‐5‐phenyloxadiazole in acetonitrile containing TEA gave an almost complete photoreduction into benzoylguanidine, while few percent of the ring photoisomer were detected. Furthermore, the pyrene‐sensitized photolysis of 3‐amino‐5‐phenyloxadiazole in acetonitrile containing triethylamine also gave benzoylguanidine but no traces of the ring photoisomer.
📜 SIMILAR VOLUMES
The photochemistry of some 1,2,4-oxadiazoles in the presence of sulphur nucleophiles has been investigated. Irradiation of the 5-amino-3-phenyl-and 3,5-diphenyl-l,2,4-oxadiazole at X = 254 nm in methanol in the presence of sodium hydrogen sulphide or thiols gave a photo-induced redox reaction at the
## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v