Gas-Phase Reaction of 1,1-Dimethylhydrazine with Nitrogen Dioxide

Article abstract of DOI:10.1021/j100232a028

The gas-phase reaction of part-per-million concentrations of nitrogen dioxide with 1,1-dimethylhydrazine in air and in N2 at 298 K was investigated by in situ long-path Fourier transform infrared (FT IP) spectroscopy.In both air and N2, the reaction occurs with an apparent overall rate constant (defined in terms of rates of hydrazine decay) of (2.3 +/- 0.2) * 10^-17 cm³ molecule^-1 s^-1.The major products were nitrous acid and tetramethyltetrazene-2, with the overall reaction stoichiometry being (CH3)2NNH2 + 2NO2 -> 2HONO + 1/2 (CH3)2NN=NN(CH3)2, regardless of initial reactant concentration ratios or whether the reaction was carried out in air or in N2.There was no observable reaction of NO with (CH3)2NNH2 in N2.However, when NO2 was also present, NO participates in the reaction, causing formation of N2O, N-nitrosodimethylamine, and significant amounts of an unidentified compound believed to be an N-nitrosohydrazine, in addition to HONO and tetramethyltetrazene-2.Probable mechanisms accounting for these observations are discussed.