Trifluoromethyl nitrate, CF3ONO2

From different routes to CF3ONO2, the reaction of CF3OF with NO2 at room te mperature under high pressure is the most favorable to synthesize CF3ONO2 i n preparative scale. The pure product is isolated for the first time after repeated trap-to-trap condensation in vacuo. CF3ONO2 is a colourless gas wi th a boiling point of -18 +/- 3 degreesC (extrapol.) and a melting point of -163 degreesC. Trifluoromethyl nitrate decays slowly into CF2O and FNO2 at room temperature in the gas phase as well as in the liquid state at lower temperatures. Furthermore, CF3ONO2 is characterized spectroscopically by NM RI IR, Raman, and UV, and structurally by gas electron diffraction and quan tum chemical calculations (B3LYP. MP2). The CF3-O bond is in the plane of t he NO3 moiety, the central CF3O-NO2 bond of 1.493(6)(A) over dot is very lo ng. The B3LYP/6-31G* calculation reproduces best the experimental data.