Generation, Microwave Spectrum, Barrier to Internal Rotation of Methyl Group, and ab Initio MO Calculation of syn-2-Nitrosopropene, syn-CH2C(CH3)NO

Sakaizumi, Takeshi; Imajo, Hirotaka; Yamasaki, R. S.; Usami, Tsuyoshi; Kawaji, Sachiko; Abe, Satoshi; Haraga, Tarou; Morii, Homura; Kuze, Nobuhiko; Ohashi, Osamu

doi:10.1006/jmsp.2000.8183

Cited by 9 publications

(2 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There is also no definitive evidence for the CH 2 C(NO)CH 3 fragment. Sakaizumi et al demonstrated that CH 2 C(NO)CH 3 gives strong signal at m / e = 71 (CH 2 C(NO)CH 3 + ) under 11.0 eV photoionization. In our experiment, however, there was no signal above background at m / e = 71 (CH 2 C(NO)CH 3 + ) using both 10.5 eV photoionization and 200 eV electron bombardment ionization, although it is possible for CH 2 C(NO)CH 3 to dissociatively ionize to m / e = 41 (CH 2 CCH 3 + ) with an appearance energy (AE) of 9.7 eV.…”

Section: Results and Analysismentioning

confidence: 99%

See 1 more Smart Citation

Elucidating the Decomposition Mechanism of Energetic Materials with Geminal Dinitro Groups Using 2-Bromo-2-nitropropane Photodissociation

et al. 2013

View full text Add to dashboard Cite

These experiments photolytically generate two key intermediates in the decomposition mechanisms of energetic materials with nitro substituents, 2-nitropropene, and 2-nitro-2-propyl radicals. These intermediates are produced at high internal energies and access a number of competing unimolecular dissociation channels investigated herein. We use a combination of crossed laser-molecular beam scattering and velocity map imaging to study the photodissociation of 2-bromo-2-nitropropane at 193 nm and the subsequent unimolecular dissociation of the intermediates above. Our results demonstrate that 2-bromo-2-nitropropane has four primary photodissociation pathways: C-Br bond fission yielding the 2-nitro-2-propyl radical, HBr elimination yielding 2-nitropropene, C-N bond fission yielding the 2-bromo-2-propyl radical, and HONO elimination yielding 2-bromopropene. The photofragments are formed with significant internal energy and undergo many secondary dissociation events, including the exothermic dissociation of 2-nitro-2-propyl radicals to NO + acetone. Calculations at the G4//B3LYP/6-311++g(3df,2p) level show that the presence of a radical at a nitroalkyl center changes the mechanism for and substantially lowers the barrier to NO loss. This mechanism involves an intermediate with a three-center ring rather than the intermediate formed during the traditional nitro-nitrite isomerization. The observed dissociation pathways of the 2-nitro-2-propyl radical and 2-nitropropene help elucidate the decomposition mechanism of larger energetic materials with geminal dinitro groups.

show abstract

Section: Results and Analysismentioning

confidence: 99%

“…There is also no definitive evidence for the CH 2 C(N O)CH 3 fragment. Sakaizumi et al 25 ) with an appearance energy (AE) of 9.7 eV. To determine whether this was occurring, we took velocity map images at m/e = 41 at 10.5 and 8.87 eV, and the two resulting speed distributions are compared in the lower frame of Figure 11.…”

Section: ■ Introductionmentioning

confidence: 99%