| The research herein investigates two primary methods to synthesize trifluoronitromethane, CF3NO2. The first method, a photochemical synthesis, was discovered by the Thrasher group and published in 2002. This photochemical method was the first one-step method for generating CF3NO 2 and uses trifluoroiodomethane, CF3I, and nitrogen dioxide, ·NO 2, as the reactants. This process is initiated by a 420 nm blue light apparatus that splits the C-I bond. The optimization and scale-up of this reaction had not been previously investigated. The production of multiple grams of CF3NO2 in a single reaction turned out to be impractical due to the equilibrium of 2 ·NO2 &rlhar2; N2O4. However, the ideal conditions for the maximum generation of CF3NO2 were found to be a total pressure of 0.3 atm, a stoichiometric ratio of 1.1 : 1 of ·NO 2 : CF3I, a temperature of at least 55°C, and a reaction time of 18 hours. Even though this method could not be scaled-up, it still represents the fastest and least expensive method for generating lab quantities of 1--3 grams of CF3NO2 via multiple reactions.;Because of the aforementioned limitations of the photochemical method, a new method for generating larger quantities of CF3NO2 had to be discovered. This new method involves the homolysis of the C-I bond in CF3I at approximately 200°C in the presence of ·NO 2 in a pressure vessel. The increase in reaction temperature allows for the previous limitations due to the 2 ·NO2 &rlhar2; N2O4 equilibrium to be overcome, allowing for larger quantities, 10--100 grams, of CF3NO2 to be produced in a single reaction. This method can be carried out over a large pressure range, 10--60 atm; similar reaction times, 18--24 hours; and with a modest increase in the yield to 35--50%. A detailed kinetics study of this new preparative route was carried out by following both the disappearance of CF3I and the appearance of CF3NO 2. The results yielded a C-I bond energy for CF3I that is in agreement with literature values. A new purification method was also developed for the larger quantities of CF3NO2, and the thermal properties of CF3NO2 were investigated using an accelerating rate calorimetry (ARC). The molecule CF3NO2 was found to be stable to almost 300°C. |
