Nitration of hydrocarbons

A. V. Topchiev, Nitration of Hydrocarbons and Other Organic Compounds., Peigamon Piess Ltd., Oxfoid, U.K., 1959. 

Titov and co-workers, although conceding the validity of the ionic nitration mechanism for liq phase nitrations with coned acids, believe that many nitrations occur via a free-radical mechanism involving the free radicals (at any rate molecules having an unpaired electron) N02, N03, and NO. For vapor phase nitration of hydrocarbons, nitration of side chains of aromatic compds in... 

Probably the main point of disagreement between the Ingold and Titov schools arises in the vapor phase nitration of hydrocarbons. Titov believes that this occurs via reaction (19), (20), (21), etc. Ingold et al (Ref 77), on the basis of some sound kinetics, propose the sequence HN03 = HO + NOp HO+ R- H20 + R R + HN03 ->RN02 (or RONO) + OH R + HNO3 -+ROH + NO2... 

The vapour phase nitration of hydrocarbons proceeds via a radical mechanism and so it is found that tertiary carbon centres are nitrated most readily, followed by secondary and primary... 

CA 70, 57139(1969) (Nitration of hydrocarbons with nitric acid—trifluoroacetic anhydride mixts)... 

There are two main theories concerning the nitration of hydrocarbons by means of the nitrating agents described above. 

A. V. TOPCHIEV, V. P, ALANYA and G. S. SHNAYDER, Dokt. Akad. Nauk AN SSSR 195, 89 (1954) A. V. TOPCHIEV Nitrovanie Uglevodorodov, p. 166. Akad. Nauk SSSR, Moscow, 2nd cd., 1966 transl. Nitration of Hydrocarbons, Pergamon Press, Oxford (1959). 

Hanson and co-workers [85] pointed out that nitro compounds with phenolic function are the main by-products of nitration of aromatic hydrocarbons. A number of papers by Dodak and co-workers [89] were dedicated to the formation of phenols in the course of nitration of hydrocarbons. However, the idea of phenols being formed through the action of NO ion does not seem to be feasible on the experimental grounds that the addition of urea to the nitrating mixture does not prevent the formation of phenols and the addition of sodium nitrite does not foster the formation of nitrophenols [85). Hanson rationalized the mechanism of formation of nitrophenols by an rpso-attack of NO on hydrocarbon (31) ... 

The problem of whether the nitration of hydrocarbons can yield dinitro compounds became controversial. According to T. Urbariski and Sfori (Vol. I. p. 95) the nitration of hydrocarbons from propane to t-heptane at 220-230 C with a great excess of NO2 can yield viscous oil containing dinitro products (10—22%... 

The nitration of hydrocarbons is carried out in a Stengel-Eagli (99] multisegment reactor (Fig. 30). It is usually composed of five segments. 

The main index headings for search other than the names of specific compounds are Paraffins nitration of Paraffins, nitro Paraffins, from nitration of— Paraffins, dinitro Hydrocaibons, nitration of Nitration of hydrocarbons Nitration of paraffins Petroleum, nitrogen compounds from Olefins, nitro derivatives and Acetylenes, nitro derivatives. These items are not mutually inclusive, e.g., references under Paraffins, nitration of are not necessarily to be found under Nitration of paraffins. In Chemical Abstracts collective index for 1937 to 1946, there are 19 entries under the first heading and 12 entries under the second only 10 are common to both lists. 

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