88718-94-9Relevant articles and documents
Photochemistry of (2-nitrophenyl)diazomethane studied by the matrix isolation technique. (Nitrophenyl)carbene to (carboxylphenyl)nitrene rearrangement by successive reduction of the nitro group with the carbenic center
Tomioka, Hideo,Ichikawa, Naoki,Komatsu, Kazunori
, p. 8045 - 8053 (2007/10/02)
Irradiation (λ > 350 nm) of (2-nitrophenyl)diazomethane (1) matrix-isolated in Ar at 10 K provided 2-nitrosobenzaldehyde (3) presumably as a result of intramolecular oxygen migration in (2-nitrophenyl)carbene (2). Upon further irradiation (λ > 350 nm), 3 was decomposed to give a mixture of 2,1-benzisoxazol-3(1H)-one (4) and carbonylcyclopentadiene imine (5) along with CO2. The oxazolone (4) underwent decarboxylation to give 5 upon irradiation with shorter wavelength light (λ > 300 nm) but not at longer wavelength (λ > 350 nm), suggesting 4 is not the direct precursor for 5 in the photolysis of 3. Irradiation (λ > 350 nm) of (4-n-butyl-2-nitrophenyl)diazomethane (1b) under similar conditions resulted in the formation of carbonyloximinocyclohexadienylidene (7) which then produced the oxazolone (4b) and the imine (5b) upon further irradiation, suggesting that a 1,4-biradical generated as a result of abstraction of H at the ortho position by the photoexcited nitroso group was involved in the reaction of 3 forming 4. (2-Carboxyphenyl)nitrene (9) generated by 1,4-OH shift in the 1,4-biradical was postulated as an intermediate leading to 5, and this was actually demonstrated by independent generation of 9 by the photolysis of 2-azidobenzoic acid (8).
