Nitrations benzene

Solutions of dinitrogen pentoxide have been used in preparative nitrations.Benzene, bromobenzene, and toluene were nitrated rapidly in solutions of the pentoxide in carbon tetrachloride nitrobenzene could not be nitrated under similar conditions, but reacted violently with solid dinitrogen pentoxide. 

First-order nitrations. The kinetics of nitrations in solutions of acetyl nitrate in acetic anhydride were first investigated by Wibaut. He obtained evidence for a second-order rate law, but this was subsequently disproved. A more detailed study was made using benzene, toluene, chloro- and bromo-benzene. The rate of nitration of benzene was found to be of the first order in the concentration of aromatic and third order in the concentration of acetyl nitrate the latter conclusion disagrees with later work (see below). Nitration in solutions containing similar concentrations of acetyl nitrate in acetic acid was too slow to measure, but was accelerated slightly by the addition of more acetic anhydride. Similar solutions in carbon tetrachloride nitrated benzene too quickly, and the concentration of acetyl nitrate had to be reduced from 0-7 to o-i mol 1 to permit the observation of a rate similar to that which the more concentrated solution yields in acetic anhydride. 

The range of preparatively useful electrophilic substitution reactions is often limited by the acid sensitivity of the substrates. Whereas thiophene can be successfully sulfonated in 95% sulfuric acid at room temperature, such strongly acidic conditions cannot be used for the sulfonation of furan or pyrrole. Attempts to nitrate thiophene, furan or pyrrole under conditions used to nitrate benzene and its derivatives invariably result in failure. In the... 

Tnflic acid is an excellent catalyst for the nitration of aromatic compounds [.S7]. In a mixture with nitnc acid, it forms the highly electrophilic nitronium inflate, which can be isolated as a white crystalline solid Nitronium inflate is a powerful nitrating reagent in inert organie solvents and in tnflic acid or sulfuric acid. It nitrates benzene, toluene, chlorobenzene, nitrobenzene, m-xylene, and benzotn-fluoride quantitatively in the temperature range of-110 to 30 °C with exeeptionally high positional selectivity [87],... 

In 1834 Mitscherlich nitrated benzene to nitrobenzene. But it is only since 1842, when Zinin reduced nitrobenzene to aniline, that rapid development of the chemistry of nitro compounds and their application to organic industry has occurred ... 

Nitrol. Early Brit plastic safety expl, patented by O. Silberrad in 1912 (Ref 2). A typical formulation is Nitrol 10, highly. nitrated benzene hydrocarbons 20, collodion cotton 0.5, and AN 69.5%. Under the same name, O. Silberrad took... 

The ease with which the sulphonic group enters into aromatic compounds depends on the nature of the substituents present, just as it does in nitration. Benzene is rather difficult to sulphonate, toluene and naphthalene are somewhat more easy, phenols and amines very easy. The sulphonation of nitrobenzene or the further sulphonation of the benzene sulphonic acids proceeds with more difficulty, and the action of the sulphuric acid must here be intensified by increasing its S03-content. 

Synonyms AI3-00808 Annulene Benxole Benzin Benzine Benzol Benzol 90 Benzole Benzolene Bicarburet of hydrogen BRN 0969212 Bz Carbon oil Caswell No. 077 CCRIS 70 Coal naphtha Coal tar naphtha Cyclohexatriene EINECS 200-753-7 EPA pesticide chemical code 008801 Mineral naphtha Mineral naphthalene Motor benzol NC1-C55276 Nitration benzene NSC 67315 Phene Phenyl hydride Polystream Pyrobenzol Pyrobenzole RCRA waste number U019 UN 1114. 

Franke patented in France in 1886, mixtures of nitrated benzene, phenol, naphthalene or naphthol with solid oxidizers, using as binders non-explosive substances, such as drying oils, soln of collodion or of gum, etc Ref Daniel, Diet (1902), 309... 

Furfuryl Alcohol Furfuryl Alcohol Furfuryl Alcohol Isoamyl Alcohol Formaldehyde Solution Gallic Acid Gallic Acid Tannic Acid Tannic Acid Benzene Hexachloride Gas Oil Cracked Copper Nitrate Benzene Hexachloride Acetic Acid Sorbitol... 

J.Harle, USP 1306895(1919) CA 13,2283(1919) (PETN alone or mixed with nitrated benzene, toluene, phenols or amines is used as a base chge for detonators) 43)W.H.Buell,USP 1308393(1919)... 

Starch was used occasionally as a binder and camphor to improve gelatinization. Some pdrs contained nitrated benzene or toluene which served as moderators of burning and as auxiliary gelatinizers. Lampblack, woodmeal, various gums... 

In the manuf of some expls, such as TNT, it is not required to calc DVS for MA, while for NG and Nitroglycol it is of great importance to know this value. For some other expls, the calcn of DVS value is optional. For example in the prepn of Dinitrobenzene by nitrating benzene with MA contg H,SO 80, HNCL 18 H,0 2% and R l.l, the DVS is 7.0, while nitration of benzene with MA contg H2 S04 60, HN03 32 ... 

Preparation 382.—Diazobenzene Nitrate (Benzene Diazonium Nitrate). C8H6.N( N).N03. C3H603N3. 167. 

Tars, Nitrated. See under Coal Tar and Coal Tar Pitch" in Vol 3, C379-R to C380-R Addnl Information Sttberrad (Refs 1 4) nitrated neutral coal tar fractions (bp 200—350°) and called the product obtained Nitrol . He claimed that it was a HE, suitable for use in expl mixts. Nitrol plasticized or dissolved such aromatic nitrocompds as TNT, TNB, etc, and was suitable for the manuf of plastic safety expls of great durability and power. A typical formulation contained Nitrol 10, a highly nitrated benzene hydrocarbon 20, collodion cotton 0.5, and AN 69.5p... 

Unfortunately, the several investigators who have examined the nitration of the halobenzenes did not adopt similar conditions. Ingold and his associates (1931) nitrated benzene and toluene by the addition of nitric acid to acetic anhydride and nitromethane. In acetic anhydride, nitric acid is slowly converted to acetyl nitrate (Bordwell and Garbisch, 1960). The relative rates, kT/kB, observed were 23 and 21 for reaction in acetic anhydride and nitromethane respectively. Bird and Ingold (1938) adopted different conditions. In a study of the halobenzenes, these workers added pre-formed acetyl nitrate to the halobenzene in acetic anhydride, acetonitrile, and nitromethane. The results for fluoro-, chloro-, and bromobenzene are summarized in Table 17 (p. 78). 

In 1950 Ingold, Hughes and Reed [39], when studying the kinetics of nitration with nitric acid in the presence of acetic acid, found the reaction to be of zero order in the case of aromatic compounds which are readily nitrated (benzene and its homologues), and its rate Va could be expressed by the approximate equation ... 

Since industrial nitration occurs, in most cases, in two-phase system a number of workers have investigated the kinetics in both phases organic and acid. Hethe-rington and Masson [84], McKinley and R. R. White [118], Barduhn and Kobe [119] all reported that nitration of aromatic hydrocarbons takes place only in the acid phase. However, other workers (W. K. Lewis and Suen [120]) have shown, when nitrating benzene, that the reaction rate in the organic phase is an appreciable fraction (10-15%) of that in the acid phase. 

An aromatic nucleus not yet substituted with the nitro group is also readily oxidized to form phenols. That is the reason why certain quantities of nitrophenols are formed when nitrating benzene to nitrobenzene, and certain nitrocresols when... 

The so-called Janovsky reaction [53] is a very characteristic one for many higher nitrated benzene derivatives. It is probably also of nucleophilic character. It consists in treating a diluted di- or tri-nitro compound solution in acetone with a concentrated solution of potassium or sodium hydroxide (generally of 30% concentration). The acetone solution turns bright coloured. Red to violet colours may appear according to the nitro compound present. 

It is characteristic that the new entrant methyl group assumes the ortho position to the nitro group and thus a substitution occurs which is similar to nucleophilic attack. Recently it has been found by Jackson and Waters [72] that higher nitrated benzene derivatives such as m- dinitrobenzene, or 1,3,5-trinitrobenzene, become homolytic hydrogen acceptors at temperatures of 80-100°C especially in the presence of the 2-cyano-2-propyl radical, which is formed by thermal decomposition of a,a -azo-bis-isobutyronitrile... 

Counter-current method. The method was suggested by Kubierschky [12]. The nitrator for nitrating benzene to nitrobenzene takes the form of a column. A mixture of nitric aid sulphuric acids is introduced at the top while a mist of hydrocarbon is fed in at the bottom. The middle part of the column plays the role... 

METHODS OF NITRATING BENZENE IN THE PRESENCE OF MERCURIC SALTS... 

Figures 8 and 9 show a m tration kettle with inner cooling, such as is used for nitrating aromatic hydrocarbons, and a separating funnel equipped with a hard lead or ceramic stopcock and having a window (lunette). The apparatus used for nitrating benzene must be completely lead lined because the spent acid is highly diluted at the end of the nitration and attacks iron.

---