title: Thermal intramolecular transformation of key intermediates in the photooxidation of para-allyl-substituted phenyl azide.
abstract: The electronic spectra, kinetic regularities, and the mechanism of decay of the cis and trans isomeric forms of 4-[(2E)-1-methylbut-2-en-1-yl]phenylnitroso oxide (2) were studied by flash photolysis and product analysis. The mechanism of the consumption of this nitroso oxide is the same as the one proposed earlier for 4-methoxyphenylnitroso oxide. The trans-2 isomer is converted into cis-2, which undergoes cyclization to the substituted benzo[d][1,2,3]dioxazole 3. The reopening of the dioxazole ring yields nitrile oxide 4. The final product (3,4-dimethyl-3a,4-dihydro-2,1-benzisoxazol-5(3H)-ylidene)acetaldehyde (5) is formed by the intramolecular [3 + 2]-cycloaddition of the nitrile oxide group of 4 to the allylic double bond. To support the proposed mechanism, the quantum chemical calculations have been employed.
authors.affiliation: Institute of Organic Chemistry, Ufa Scientific Center, The Russian Academy of Sciences, 71 prosp. Oktyabrya, 450054 Ufa, Russian Federation. kinetic@anrb.ru
authors.forename: Ekaterina M
authors.initials: EM
authors.lastname: Chainikova
authors.forename: Evgeniy Yu
authors.initials: EY
authors.lastname: Pankratyev
authors.forename: Aigul N
authors.initials: AN
authors.lastname: Teregulova
authors.forename: Rail R
authors.initials: RR
authors.lastname: Gataullin
authors.forename: Rustam L
authors.initials: RL
authors.lastname: Safiullin