Photooxidation of CF3CF2C(O)Cl in the presence of NO2. Synthesis and characterization of pentafluoroethyl peroxynitrate, CF3CF2OONO2

The photolysis of CF3CF2C(O)Cl in the presence of NO2 and O2 at 254 nm leads initially to the formation of CF3CF2OONO2, CF2O, and CO as the main carbonaceous products. The NO2 concentration governs the identity of the products. As photolysis continues the NO2 concentration gradually decreases until new channels open up and the mechanism leads to the formation of CF2O, CO2 and CF3OC(O)OONO2.In addition to the study of the mechanism, we present in this paper some characteristics of the pentafluoroethyl peroxynitrate, CF3CF2OONO2 such as the infrared spectrum with the associated absorption cross-sections for the main peaks and kinetic parameters for its thermal decomposition at total pressures of 9.0 and 250 mbar (Ea = 87.7 kJ/mol, A = 3.8 × 1013; and Ea = 96.7 kJ/mol, A = 2.37 × 1015, respectively) which show that they are dependent both on the temperature and on the total pressure.

► New peroxynitrate has been synthesized.
► Thermal stability of pentafluoroethyl peroxynitrate CF3CF2OONO2 was measured.
► Reaction mechanism of photooxidation of CF3CF2C(O)Cl in the presence of NO2 was determined.