Nitration alkane with

Aliphatic Nitration. Alkanes undergo electrophilic nitration with nitronium salts such as (N02) piotic solvent such as CH2CI2... 

The kinetics and mechanism of iV-nitration reactions have been reviewed and the nitration of alkanes with nitronium hexafluorophosphate in CH2CI2 or EtN02 has been shown to involve direct electrophilic insertion of NO2+ into C-H and C-C a-bonds. ... 

Dinitrogen pentoxide reacts with alkanes in carbon tetrachloride at 0 °C via a radical mechanism to give nitration products which can include nitrate esters.Reactions of alkanes with dinitrogen pentoxide in nitric acid are complex and of little synthetic value. 1-Adamantyl nitrate is one of the products obtained from the photochemical irradiation of a solution of adamantane and dinitrogen pentoxide in methylene chloride. ... 

Efficient catalytic alkane nitrations can be performed with the assistance of N-hydroxyphthalimide (NHPI) with N02 in air [Eq. (10.57)]298 or with HNO3.299 NHPI may also be used to form alkanesulfonic acids by reacting alkanes with S02 300... 

Electrophilic nitration of alkanes has been performed with nitronium salts, for example, NO2 PFe and with HNO3-H2SO4 mixtures, but mixtures of nitration and cleavage products are obtained and yields are generally low. ° The reaction of alkanes with nitric acid and A-hydroxysuccinimide (NHS), however, gave moderate-to-good yields of the corresponding nitroalkane. Similar nitration was accomplished with NO2, NHS and air. "... 

As is known (Vol. I). alkanes can be nitrated in vapour phase by nitric acid or nitrogen dioxide. Nitration with nitric acid at temperatures of 400-435 C (method of Hass, Vol. I. p. 86) became a well established commercial method of making nitroalkanes. A considerable number of papers mainly by Hass and co-workers (Vol. 1) and Titov (Vol. I) gave both theoretical and practical foundations for this remarkable process and subsequently less theoretical work has appeared. Less attention was paid to the nitration of alkanes with nitrogen... 

The reaction proceeds smoothly in alkaline aqueous media with silver nitrate and inorganic nitrites. Because of this method reuci ami colleagues 1131 ] weic able to obtain a. o. ui. co-tetranitru alkanes. With four carbon atoms of chain ol the nitroalkane. the yield of tetranitro com)>ouiKl could reach... 

As far as nitration with liquid N2O4 is concerned, attention should be paid to the danger of keeping solutions of alkanes with Nj O4. 

The first examples of the conversion of nitroalkanes to carbonyl compounds were described in 1893 by Konovaloff, who was examining the reactivity of nitroalkanes obtained from nitration of alkanes with nitric acid.1 Konovaloff reported that treatment of 2-nitrohexane (3) with strong soda (NaOH) followed by reaction with Zn/HOAc afforded a mixture of methyl butyl ketone (4) and 2-aminohexane (5). Additionally, the reaction of the potassium salt of 2-phenylnitroethane with dilute aqueous acid provided mixtures of acetophenone and 2-phenylnitroethane. 

The products of these reactions are carbocations or olefins which are in equilibrium with the carbocations. Mechanisms involving structures VIII-13-VIII-14 can be only hardly discriminated. The only evidence for the mechanism of electrophilic substitution might be the deep similarity in selectivity and KIE for the reactions between palladium(ll) and alkanes on the one hand, and nitration of alkanes with NOz on the other hand. Indeed, such a similarity has been evaluated in the study of the temperature dependencies of KIE and 5/6 effects. 

TABLE 6.19 Rate Constants at 25° C for Reactions of Hydroxyl and Nitrate Radicals with Alkanes... 

HF and HSO3F (or other superacid) solutions (see subsequent discussion). Higher alkanes and isoalkanes gave yields of 5-10% and adamantane was nitrated in 30% yield. Data indicate that nitratioa (nitrolysis) of alkanes with nitronium salts proceeds in accordance with the generalized concept of electrophilic reactions of single bonds [77] involving two-electron, three-center bond carbocationic intermediates (transition states) as illustrated with case of the nitration of methane. 

The nitrate esters have also been used in human health and medicine fields [9, 10]. For example, single alkane nitrates play an important role in clearance and purification of energy and environment [11, 12]. There are about 20 liquid nitrate esters with most bright potential in application and production over the world. They will be introduced in the following sections. 

Temperature dependence of reactions of the nitrate radical with alkanes, in G. Restelli, G. Angeletti (eds). Fifth European Symp. on Physico-Chemical Behaviour of Atmospheric Pollutants, Kluwer Academic PubL, Dordrecht 1990, pp. 328-333. 

Temperature dependence of reactions of the nitrate radical with alkanes,... 

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... 

The initiation of radical formation in the gas-phase nitration of alkanes with NO is closely related to other phenomena connected with the catalysis of the reaction by chlorine [10], bromine [11], iodine [11], and mixtures of these halogens with oxygen. The observed accelerating effects of small additions of halogens with their initiation of radical formation can be represented by the scheme [10] ... 

In the course of gas-phase nitration of alkanes with NO, increase in the yield of nitroalkane can be attained by increase in the rate of radical formation and retardation of oxidative reactions in which the free radicals take part. It is probable that the catalytic effect of molecnlar iodine on the nitration of propane with NO is associated mainly with the tendency of inactive iodine atoms to retard the oxidation of hydrocarbons [11]. In the presence of 0.15% I, the CO content of the reaction products is reduced from 22.1 % to 5.2%. Simultaneously, the yield of nitro compounds is increased by 10%. 

Thus, the rate-determining step of alkane nitration is the formation of free alkyl radicals in (Equation 5.1), as well as in reaction of alkanes with O, NO3, OH, Cl and other active radicals. The reactions of R with NO, NO, O, N O [19], Br [20] and other components of the reaction system (including solvents) results in a mixture of nitro compounds, nitrites, nitroso compounds, and nitrates. All these compounds with the exception of RNO depending on the conditions undergo further conversions, resulting in the different composition of the end products of nitration. 

Treatment of 3-methylquinoline (10) by the NHPI-Co-Mn system under the readion condition used for P-picoline, however, results in the recovery of the starting 10. This is believed to be because the activation of O2 by the Co(II) becomes difficult, probably because of coordination of 10 to Co(OAc)2. As described below, the nitration of alkanes with NO2 is enhanced in the presence of NHPI catalyst, in which... 

The basis of the chemistry included in the GEOS-Chem model (Bey et al., 1999) was described by Horowitz et al. (1998). The mechanism includes explicit chemistry for methane, ethane, propane, butane, propene, and isoprene. Butane is used as a surrogate for all alkanes with carbon number > 4 and propene for alkenes > 3. This approach is based on the similarities in the yields per carbon atom of O3, HOjt (OH, HO2, RO2) and peroxyacyl nitrates for these compound classes, as discussed by Jacob et al. (1989). Three peroxyacyl nitrates PAN, PPN (a lumped peroxyacyl nitrate) and PMN (peroxymethacryloyl nitrate) are included, together with ISN2, a lumped organic hydroxynitrate, required for the isoprene mechanism and R4N2, a lumped alkyl nitrate. Seven carbonyl species are included formaldehyde, acetaldehyde, methacrolein, other aldehydes (RCHO), acetone, methylvinyl ketone, and other ketones (MEK). 

Adams catalyst, platinum oxide, Pt02 H20. Produced by fusion of H2PtCl6 with sodium nitrate at 500-550 C and leaching of the cooled melt with water. Stable in air, activated by hydrogen. Used as a hydrogenation catalyst for converting alkenes to alkanes at low pressure and temperature. Often used on Si02... 

The selection of solvents for quantitative work is not easy. Nitro-alkanes are sufficiently inert, but nitronium tetrafluoroborate is poorly soluble in them c. 0-3 %). Nitronium salts react rapidly with acetic anhydride, and less rapidly with acetic acid, A, A -dimethylformamide and acetonitrile, although the latter solvent can be used for nitration at low temperatures. Sulpholan was selected as the most suitable solvent ... 

The only method utilized commercially is vapor-phase nitration of propane, although methane (70), ethane, and butane also can be nitrated quite readily. The data in Table 5 show the typical distribution of nitroparaffins obtained from the nitration of propane with nitric acid at different temperatures (71). Nitrogen dioxide can be used for nitration, but its low boiling point (21°C) limits its effectiveness, except at increased pressure. Nitrogen pentoxide is a powerful nitrating agent for alkanes however, it is expensive and often gives polynitrated products. 

Alkanes can be nitrosated photochemically, by treatment with NOCl and UV light. For nitration at an activated carbon, see 14-12. 

Organic synthesis 51 [OS 51) Nitration of alkanes such as methane and hexane with... 

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