Photochemical transformations of the azidonitroxyl radical in glassy media

The kinetic characteristics of the photochemical decomposition of the azido group of 3-azido-4-hydroxyimino-2,2,6,6-tetramethylpiperidine-1-oxyl in solid matrices at 293 and 77 K were studied. It was revealed that the presence of the nitroxyl radical center in the molecule is responsible for the realization of the radical mechanism of the decomposition of the azido group. The values of the quantum yield φ of the decomposition of the azido group were found to be 0.056 in toluene at 77 K, 0.14 in polystyrene at 77 K, and 0.16 in polystyrene at 293 K. It was demonstrated that the number of radicals remaining after photolysis correlates with the molecular mobility of the medium.