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Mononitro compounds

A mixture of the two mononitro-chlorobenzenes is prepared by nitration of chlorobenzene. Further nitration of the mixture or of either of the mononitro-compounds gives 2,4-dinitrochlorobenzene, m.p. 5 C, b.p. 315"C. [Pg.277]

Quantitative estimation of cyclohexane in the presence of benzene and aUphatic hydrocarbons may be accompHshed by a nitration-dehydrogenation method described in Reference 61. The mixture is nitrated with mixed acid and under conditions that induce formation of the soluble mononitroaromatic derivative. The original mixture of hydrocarbons then is dehydrogenated over a platinum catalyst and is nitrated again. The mononitro compounds of the original benzene and the benzene formed by dehydrogenation of the cyclohexane dissolve in the mixed acid. The aUphatic compound remains unattacked and undissolved. This reaction may be carried out on a micro scale. [Pg.409]

In additionto the mononitro compounds, monohydric and dihydric dinitro alcohols have been prepared but are not available commercially. The formation, properties, and reactions of nitro alcohols have been reviewed (1,2). [Pg.60]

In addition to neutralization, prolonged action of alkaline reagents can effect oxidation—reduction and extensive decomposition. 1,1-Dinitroparaffins and trinitromethane are more stable than are mononitro compounds during neutralization and subsequent regeneration, and therefore more rigorous experimental conditions are permissible. [Pg.99]

The impurities present in aromatic nitro compounds depend on the aromatic portion of the molecule. Thus, benzene, phenols or anilines are probable impurities in nitrobenzene, nitrophenols and nitroanilines, respectively. Purification should be carried out accordingly. Isomeric compounds are likely to remain as impurities after the preliminary purifications to remove basic and acidic contaminants. For example, o-nitrophenol may be found in samples ofp-nitrophenol. Usually, the ri-nitro compounds are more steam volatile than the p-nitro isomers, and can be separated in this way. Polynitro impurities in mononitro compounds can be readily removed because of their relatively lower solubilities in solvents. With acidic or basic nitro compounds which cannot be separated in the above manner, advantage may be taken of their differences in pK values (see Chapter 1). The compounds can thus be purified by preliminary extractions with several sets of aqueous buffers... [Pg.67]

Aliphatic fluorodenitration has also been applied to mononitro compounds, specifically to an a-nitroepoxide Thus, l,2-anhydro-3 4 5,6-di-O isopropyli dene-1-C-nitro D mannitol and labeled potassium bifluonde give 2-deoxy-2-fluo-ro-3,4 5,6-di-O-isopropylidene aldehydo D glucose [J03, 104] (equation 30)... [Pg.286]

Nitration of quinindoline gave the expected 9-nitro derivative (261). A single mononitro compound was formed from the 3,4-dihydro-jS-carboline, harmaline this was 6-nitroharmaline, since on oxidation it yielded 3-nitro-4-methoxybenzoic acid. [Pg.144]

Nitration of 5-(4-chiorophcnyl)-l//-l,4-benzodiazepin-2(3//)-one gives either a mono- or a dinitro derivative 16a or 17a, depending on the amount of the nitrating agent.226 The 5-(4-methoxyphenyl) analog yields either a mixture of two isomeric mononitro compounds, which cannot be separated, or, with an excess of nitrating agent, a dinitro derivative 17b. [Pg.404]

Total acid phase, 4 kg/hr, 2.395 liters/hr Find the size of reactor and the residence time for 90% conversion of the toluene assuming it all goes to the mononitro compound. [Pg.846]

Nitration of 2-bromodibenzothiophene 5,5-dioxide gave a mononitro compound tentatively assumed to be the 7-nitro isomer enlarged preparative details of the known 8-nitro-2-bromodibenzothiophene were also described. ... [Pg.262]

The next problem with this reaction is that the mononitro compound can add successive nitro groups to produce the di- and trinitro toluenes in the reactions. Fortunately, the rate coefficients for adding the second and especially the third nitro groups are much smaller than for adding the first so mononitrotoluene can be made with good efficiency by simply heating toluene in nitric acid (Figure 3-19). [Pg.125]

Aliphatic Nitro Compounds The molecular ion peak (odd number) of an aliphatic mononitro compound is weak or absent (except in the lower homologs). The main peaks are attributable to the hydrocarbon fragments up to M — N02. Presence of a nitro group is indicated by an appreciable peak at m/z 30 (NO+) and a smaller peak at mass 46 (N02+). [Pg.31]

D-Mannitol hexanitrate crystallizes from ethyl alcohol in the form of needles melting at 112-113°C. Its specific gravity is 1.604. It is immiscible with water, dissolves readily in ether and hot ethanol and with difficulty in cold ethyl alcohol. With aromatic mononitro compounds, e.g. nitrobenzene, p-nitrotoluene, p-nitroanisole, a-nitronaphthalene, mannitol hexanitrate forms addition compounds melting in a non-homogeneous way, as shown by T. Urbanski [5, 6, 7, 17]. [Pg.169]

Mononitro compounds could be selectively obtained in the nitration of phenyl-propiolic acid derivatives with HNO3-HSO3F at low temperature501 [Eq. (5.191)]. Addition of fluorosulfuric acid to the triple bond, however, may also take place with substituted derivatives. [Pg.642]

Aromatic mononitro compounds may sometimes be characterised by conversion into the corresponding dinitro or trinitro derivatives. It may be noted that many poly-nitro compounds form characteristic addition compounds with naphthalene. [Pg.1282]

Nitration of 2-methyl-3-phenylindole using potassium nitrate in sulfuric acid also yields a mixture of 2-methyl-3-(4-nitropheny )indole (13%) and 2-methyl-5-nitro-3-(4-nitrophenyl)indole (2%). This dinitro product is also obtained by a second nitration of the mononitro compound. However, nitration of 3-methyl-2-phenylindole under these conditions gives only the 5-nitro derivative (80%) with no nitration in the phenyl ring. [Pg.222]

Table 5.1 shows the results of the chemical assembly of compounds 2 and 3 using the two different deprotection techniques. As shown in the Table, under both basic and acid catalyzed conditions, mononitro compound 2 formed SAMs that are consistent with its theoretical calculated thickness. On the other hand, SAMs of compound 3 formed thinner layers under basis conditions and thicker layers under acid conditions when compared to the theoretical values. The thinner layer might be due to the formation of bond angles smaller than 180° or to incomplete SAM formation the thicker layer is likely a multi-layer. [Pg.84]

More reactive than mononitro compound, but—NO2 group is ortho to azide (see Ch.3)... [Pg.191]

Shaw calculated the isokinetic point between homolysis and elimination as 770K for mononitro- and vicinal dinitro-alkanes and as 370K for gem-dinitro species [51]. In gem-polynitro species the C-N02 bond is weaker than in mononitro compounds due to inductive effects [52] thus, homolysis is thought to be the principal decomposition pathway in 2,2 dinitropropane and hexanitroethane [48]. Octanitrocubane has recently been synthesized (Fig. 6). Its crystal density was lower (1.979 g/cm3) than the predicted 2.1 [53]. Like hexanitrobenzene, octanitrocubane has a perfect oxygen balance, but at this point it appears unlikely that further development of this compound will be undertaken. [Pg.15]

Trinitro to a Mononitro- compounds Naphthalene e- MNN See under parent compds No color No color ... [Pg.191]

Nitration of aromatic hydrocarbons with a side chain gives mononitro compounds with the nitro group attached either to the ring or to the side chain, with a predominance of the former. For example, from toluene at temperature 14-15°C, 46% of nitrotoluenes and 9% of phenylnitromethane were obtained. [Pg.93]

Brand Mid his co-workers [17] CMiied out extensive studies on the absorption spectra of Momatic compounds in sulphuric acid solutions, i.e. in a strongly proto-nizing solvent. They found that under the influence of the sulphuric acid the maximum of the nitro group shifted. These shifts were most pronounced in the case of mononitro compounds, Mid the least in the case of trinitro compounds. They were smaller when sulphuric acid was used as a solvent, Mid larger when oleum was used. The absorption curves for 2,4-dinitrotoluene Me shown in Fig. [Pg.173]

Both cryometric (Gillespie [60]) and spectrographic (Brand, Homing and Thom-ley [17]) investigations of nitro compounds indicate that in sulphuric acid solutions mononitro compounds behave like weak bases (p. 174). Thus it follows from cryometric measurements that nitromethane in 100% sulphuric acid solution is 20% ionized, and nitrobenzene 40%. Nitrobenzene is a stronger base than nitromethane. [Pg.184]

For this reason, mononitro compounds will be described only from the viewpoint of their utilization as intermediates for the preparation of higher nitrated products. [Pg.188]

As shown by T. Urbanski [143] between 1933 and 1937, there is a group of molecular addition compounds whose existence cannot be explained by all the points mentioned above. They are addition compounds of certain nitro compounds with esters of nitric acid. Thus many aromatic mononitro compounds form addition compounds with mannitol hexanitrate, and some aromatic trinitro compounds do so with erythritol tetranitrate (Vol. II). On the basis of these facts the author suggests that two main reasons are responsible for the formation of these addition compounds ... [Pg.224]

All three isomers are pale yellow substances, with the smell characteristic of mononitro compounds. They are soluble in most organic solvents. The solubility of technical MNT in sulphuric acid is shown in Table 46. Due to the presence of a methyl group, the isomers are much less toxic than nitrobenzene (p. 260). [Pg.269]

Medard [43] has examined the explosive properties of nitropolystyrene containing 13.9% of N, i.e. consisting of about 90% of the dinitro and 10% of the mononitro compound. In his investigations he compared nitropolystyrene with dinitrotoluene and found the former to be a less powerful explosive and less sensitive to impact. [Pg.419]

Mononitro compound 26 (Scheme 11) required several hours of heating to effect complete rearrangement into 27 [20]. The dinitro derivative 28 under analogous conditions rearranged to 29 in 15 min. Transformation 30 to 31 occurred in 4 h. In the later case, the six-membered spiro-intermediate was involved. [Pg.170]


See other pages where Mononitro compounds is mentioned: [Pg.23]    [Pg.404]    [Pg.373]    [Pg.525]    [Pg.123]    [Pg.877]    [Pg.235]    [Pg.257]    [Pg.77]    [Pg.114]    [Pg.496]    [Pg.33]    [Pg.124]    [Pg.23]    [Pg.153]    [Pg.289]    [Pg.496]   
See also in sourсe #XX -- [ Pg.134 ]




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