Long pathlength/FTIR smog chamber techniques were used to determine the Cl atom initiated atmospheric oxidation mechanisms for methoxyflurane (CH₃OCF₂CHCl₂) in 700 Torr of air or O₂ diluent at 296 K. The oxidation of CH₃OCF₂CHCl₂ in both air and O₂ diluent gave one primary carbonyl-containing product in approximately 100% yield and one secondary bi-carbonyl product in addition to COF₂ and COCl₂, the latter two both with initial molar yields of 2 ± 1%. A mechanism is proposed for the oxidation of methoxyflurane which explains the observed product distribution. IR spectra for HC(O)OCF₂CHCl₂ and HC(O)OCF₂C(O)Cl are calculated and reported.