Properties and Thermal Decomposition of the Hydro-Fluoro-Peroxide CH3OC(O)OOC(O)F

Abstract

The thermal decomposition of methyl fluoroformyl peroxycarbonate CH3OC(O)OOC(O)F was studied in the range of 30– 96 °C using FTIR spectroscopy to follow the course of the reaction in the presence of either N2, O2, or CO as bath gases. The rate constants of the homogeneous first-order process fit the Arrhenius equation kexp = (5.4 ± 0.2) × 1014 exp[−(27.1 ± 0.6 kcal mol–1/RT)] (in units of s–1). A complete mechanism of decomposition is presented. An experimental O–O bond energy of 27 ± 1 kcal mol–1 was obtained. The products observed when N2 or O2 are used as bath gases were CO2, CO, HF, and CH3OC(O)H, while in the presence of CO, CH3OC(O)F was also observed. Transition state ab initio calculations were carried out to understand the dynamics of the decomposition. Additionally, thermodynamic properties of the atmospherically relevant CH3OCO2• radical were calculated. The heat of formation, ΔH°f 298, obtained for CH3OCO2• and CH3OC(O)OOC(O)F, were 78 ± 3 kcal mol–1 and 191 ± 5 kcal mol–1, respectively.