Reactions of NO2 with Alkanes

It is considered [3-6] that when NO is used as a nitrating reagent, the following 

The vapour-phase nitration of alkanes with NO is usually carried out in a reactor at 250-350 °C. In view of the partial dissociation of NO which undoubtedly occurs under these conditions, the primary radical formation can be explained on the basis of the reaction of oxygen formed by the dissociation of NO with the alkane by the 

It is also assumed that the oxidation of hydrocarbons is initiated by oxygen atoms formed by the thermal dissociation of a nitrogen oxide (NO) [3]. The use of gaseous initiation of liquid-phase oxidation of paraffins (127 C), consisting of addition of NO to air at the beginning of the reaction, allows considerable shortening of the induction period for the oxidation [9], With a 30-minute initiation by air containing 0.35% NO, the induction period is 10 hours, as compared with 366 hours in the absence of the initiator. 

Data obtained for the nitration of propane with NO in the gas phase at 300 C in the presence of oxygen shows [3] that a rise in oxygen concentration in the reaction zone by increasing the opportunities for radical formation appreciably increases the yield of nitroalkanes. If the same process is carried out at 350 C, there is a sharp fall in the yield and extent of conversion, and there is an appreciable increase in the carbon monoxide (CO) content of the exit gases. It would appear that, in the high-temperature nitration of alkanes, conditions are created under which the rate of the reaction  

One of the possible causes of the development of an oxidative course in the nitration lies in the thermal decomposition of nitrocompounds and alkyl nitrites [4]. RONO decomposes between 300 °C and 500 °C. For instance, ethylnitrite produces a free 

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