The thermal decomposition of nitroethane and 1-nitropropane

Abstract

The thermal decomposition of nitroethane has been studied by a static method over the temperature range 355-405' C, and shown to be a largely homogeneous reaction of the first order in the pressure range 50-300 mm. Under the conditions used, the extent of heterogeneous reaction was estimated to be about 10 yo, with the consequence that the estimated equation for the rate constant of the homogeneous reaction, k = 1 0 ~3 ' ~ e-47,000/aT sec.-l, is subject to an uncertainty which is not easy to estimate. The activation energy is, however, unlikely to be in error by more than 2 kcal. The main gaseous products are ethylene and nitric oxide, with some oxides of carbon. I-Nitropropane, which was studied in less detail, has an activation energy of about 5 0 kcal., and the products include propylene. The mechanism is considered to be a unimolecular reaction to give the olefin and HNO,, followed by oxidation of some of the olefin.

The influence of molecular structure on the change of the arrhenius factor of gas‐phase elimination of nitric acid from nitroalkanes

“…The reaction of elimination is one of the main mechanisms of the gas‐phase monomolecular decomposition of aliphatic nitrocompounds 8–12. It was reliably established that nitroethane and most of other mononitro‐ and halide mononitroalkanes decompose according to this mechanism 13.…”

Photochemical production of alkyl and alkoxyl radicals and their reactions with oxygen

“…similar mechanism was proposed by Brown and Pimentell6 for the low-temperature photolysis of nitromethane, but Pimentel and Rollefson 17 favour (10) as the primary process in the gas-phase photolysis of nitromethane and this is supported by Nicholson 18 and Bielski and Timmons.19 An initial step involving intramolecular elimination has been adopted by Wilde 20 and Cottrell, Graham and Reid21 for the thermal decomposition of nitroethane :…”

“…should occur readily. Reaction(21) is about 33 kcal endothermic. Because of the considerable temperature rise resulting from the sequence (1 7), (1 8),…”

Density functional study of the decomposition pathways of nitroethane and 2-nitropropaneElectronic supplementary information (ESI) available: The structure of minima on the PES of nitroethane (Fig. S1) and 2-nitropropane (Fig. S2). See http://www.rsc.org/suppdata/cp/b3/b300275f/

“…The decomposition of organic molecules containing one or more nitro groups has been the subject of much research since long ago. Early studies (before 1960 [1][2][3][4][5] ) were devoted to analyse the pyrolysis of nitropropanes. In 1967, Spokes and Benson 6 published a very low-pressure pyrolysis study of the decomposition of nitroethane (1) and 1-and 2-nitropropane (2).…”