I Nitromethane

Example 12.4 Influence of the Environment on D i. Nitromethane is interesting to some people because it explodes. The reason is, of course, in the cleavage of the carbon-nitrogen bond. The monomer, compared to its trimer (taken as a model for the crystal), reveals that the C and N net charges change by A c — 8.7 and A n—1-1 me. respectively, on crystallization. Our bond energy formula and the appropriate parameters thus indicate that the crystalline environment reinforces the CN bond by 4.7 kcal/mol, which is significant at the local point of rupture, responsible for the reaction [251]. 

Figure 2. X-ray fiber diffraction patterns for ("top, left to right) V -amylose VrnlSo-amylose KOH-amylose (bottom, left to right) B-amylose, amylose triacetate I, triethylamylose I-nitromethane complex...

What would be the N chemical shift of acetonitrile (H3CCN) if, instead of (CH3)4N+I, nitromethane (CH3NO2) were used as internal standard (See Figure 7.5.)... 

Figure ii-l Pxy graph (left) and Txy graph (right) of the system acetonitrile (i)-nitromethane (2) calculated using Raovdt s law. 

Marsh, K. N. French, H. T. Refers, H. P. Excess Gibbs free energy for cyclohexane -i- nitromethane, -i- nitroethane, + 1-nitropropane, and -i-2-nitropropane at 318.15 K/. Chem. Thermodyn. 1979,11, 897-903... 

Much of the early work was inconclusive confusion sprang from the production by the reaction of water, which generally reduced the rate, and in some cases by production of nitrous acid which led to autocatalysis in the reactions of activated compounds. The most extensive kinetic studies have used nitromethane,acetic acid, sulpholan,i and carbon tetrachloride as solvents. 

The relative abilities of nitromethane, sulpholan, and acetic acid to support the ionisation of nitric acid to nitronium ions are closely similar to their efficiencies as solvents in nitration. Raman spectroscopy showed that for a given concentration of mixed acid (i i nitric and sulphuric acids) the concentration of nitronium ions in these three solvents varied in the order nitromethane > sulpholan > acetic acid. The concentration of mixed acid needed to permit the spectroscopic detection of nitronimn ions was 25 %, 50 % and 60 % in the three solvents, respectively (see 4.4.3). 

The use of i i mixed aeid in sulpholan and in aeetie acid was examined (table 4.1, eolumns (/)-(i))- The variation of the eoncentration of nitronium ions with the eoneentration of mixed aeids ([H2SO4] [HNO3], 1 1), in sulpholan (a), aeetie aeid (6), and nitromethane (c) are illustrated in fig. 4.1. The results for aeetie aeid and sulpholan were determined by Raman speetroseopy, and those for nitromethane from the infra-red speetra. 

Fig. 4.1. Variation of NO2+ ion concentration with the concentration of mixed acid (nitric sulphuric, i mole i mole) inorganic solvents (a) in sulpholan (6)in aceticacid (c) in nitromethane. Curves (a) and (6) were determined by Raman measurements using the 1400 cm band while curve (c) was derived from infra-red measurements on the 237s cm band. Unity on the NO2+ concentration scale was determined to be 5-6 molar ( 2S 8 weight %). (From Olah et...

For the nine substituents m- andp-methyl, p-fluoro, m- and p-chloro, m- and p-bromo, and m- and p-iodo, using the results for nitration carried out at 25 °C in nitromethane or acetic anhydride - (see tables 9.1, 9.5), a plot of logjoA/ j against cr+ produced a substituent constant p = —6-53 with a standard deviation from the regression line i = 0-335, 2 correlation coefficient c = 0-975. Inclusion of... 

Thompson points out that there is no evidence that adducts give other than acetates on thermolysis. The exocyclic methylene intermediate (iv) postulated by Robinson could arise by proton abstraction from a Wheland intermediate analogous to (vll) above, rather than from the adduct (in). Similarly its decomposition does not necessarily require the intermediacy of the adduct (v). The fact that i -methyl-4-nitromethylnaphthalene is the product even when the nitrating medium is nitric acid and nitromethane would then require no separate explanation. 

First, your Nitromethane may require purification, especially if it w/ as for "fuel" use. In this case, it needs to be vacuum distilled at a vacuum of better than 100mm Hg. At that pressure, it will come off at 47C. Distillation at atmospheric pressure is possible, but I do not recommend it due to the highly flammable nature of the compound and because it s flash point is 42C. It s your choice. 

The acid chloride of i i7-nitromethane, CH2=N(C1)0 (mp —43°C, bp 2—3°C), is formed by fusion of nitromethane and picrylpyridinium chloride (36). It is hydroly2ed to nitro some thane, reduces potassium permanganate strongly, and exhibits no reactions characteristic of hydroxamic acids. 

The reaction rates of toluene and benzene with i-propyl chloride in nitromethane fit a third-order rate law ... 

Molecules that possess more than one nucleophilic si are referred to as ambident nucleophiles. Sn2 reactioi involving these nucleophiles may lead to mixtures i products. For example, nucleophilic attack by nitrite c methyl bromide gives both nitromethane and methyl nitrit... 

Figure 7. Infrared spectrum of pyrethrin I Isolated after dual partition chromatography First partition column. Celite-acetonitrile-hexane Second partition column. Silicic acid-nitromethane-hexane (with 5% acetone). Corresponds to peak 3 of gas chromatographic separation of pyrethrum mixture...

I. Brown and F. Smith, "Liquid-Vapor Equilibriums. VI. The Systems Acetonitrile-Benzene at 45° and Acetonitrile-Nitromethane at 60c". Ansi. J. Chem., 8, 62-67 (1955). 

Studies of the relative rates of the zinc chloride-catalysed bromination of alkyl-and halogeno-benzenes in nitromethane at 25 °C have lead to the suggestion that the rate-determining step of the reaction is formation of Ji-complex, since low substrate selectivity was found to be coupled with high (i.e. normal) positional selectivity323. Under some conditions (column 1 in Table 75) the low selectivity... 

Relative rates of alkylation of toluene and benzene using a mixture of nitro-sonium hexafluorophosphate, nitromethane (or acetonitrile) and aliphatic amine as the alkylations agent have been determined at 25 °C as follows360 1.5 (ethyl-amine), 2.5 (i-propylamine) and 3.5 (benzylamine) nothing more as yet is known about the kinetics of alkylation with these new alkylating reagents. 

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