35310-31-7Relevant academic research and scientific papers
Ion-Molecule Reactions of CF3+ with Simple Unsaturated Aliphatic Hydrocarbons at Near-Thermal Energy
Tsuji, Masaharu,Aizawa, Masato,Nishimura, Yukio
, p. 3195 - 3200 (2007/10/02)
Ion-molecule reactions of CF3+ with C2H2, C2H4, and C3H6 have been studied at near-thermal energy (0.05 eV) by using an ion beam apparatus.Initial product ion distributions and reaction rate constants were determined and compared with previous beam and selected ion flow tube (SIFT) data.The CF3+/C2H2 reaction produces exclusively the electrophilic adduct C3H2F3+ ion.For C2H4 and C3H6, hydride abstraction and electrophilic addition followed by HF elimination or fluoride transfer occur in parallel.The branching ratios of the former and latter reactions are 0.29 +/- 0.04:0.71 +/- 0.06 for the CF3+/C2H4 reaction and 0.07 +/- 0.02:0.93 +/- 0.07 for the CF3+/C3H6 reaction.On the basis of theoretical calculations of potential energies for the CF3+/C2H2 and CF3+/C2H4 systems, the lack of the HF elmination channel in the CF3+/C2H2 reaction, whereas the lack of the initial adduct ion in the CF3+/C2H4 reaction, is attributed to the different stability of the intermediate adduct ions for HF elimination.The reaction rate constants were 0.45 x 1E-9, 1.3 x 1E-9, and 1.6 x 1E-9 cm3 s-1 for C2H2, C2H4, and C3H6, respectively, which correspond to 46percent, 120percent, and 130percent of calculated rate constants from Langevin theory or a parametrized trajectory model.Although there are significant discrepancies in the product ion distributions between the present beam experiment and the previous beam data, the product ion distributions and the reaction rate constants obtained here are in reasonable agreement with the previous SIFT data.
Translational Energy-Resolved Collisionally Activated Methyl Cation Transfer from Protonated Methane to Argon, Krypton, and Xenon and from Protonated Fluoromethane to Argon and Molecular Oxygen
Heck, Albert J. R.,Koning, Leo J. de,Nibbering, Nico M. M.
, p. 8870 - 8876 (2007/10/02)
Translational energy-resolved collisionally activated gas-phase reactions of protonated methane with argon, krypton, and xenon and of protonated fluoromethane with argon and molecular oxygen are studied using the method of Fourier transform ion cyclotron resonance mass spectrometry.It appears that translationally activated protonated methane can act as a methyl cation donor if the competing proton transfer is energetically less favored.Translational energy-resolved collisionally activated reactions between protonated methane and argon, krypton, and xenon reveal that the methyl cation transfers resulting in the formation of methylargonium, methylkryptonium, and methylxenium ions all proceed via transition states which are about 0.6 eV higher in energy than the reactants.The results suggest that in these transition states the weakening of the two-electron three-center C-H-H bond in protonated methane is more advanced than the bond formation between the methyl group and the noble gas atom.Similarly, translationally activated protonated fluoromethane can transfer a methyl cation to argon and molecular oxygen via transition states which are about 0.3 and 0.4 eV higher in energy than the reactants, respectively.It is shown that the product ion from the methyl cation transfer from protonated fluoromethane to molecular oxygen has the methylperoxy cation structure.
