Sciencemadness Discussion Board

1,4-dichlorobenzene nitration(moth balls)

niertap - 11-4-2012 at 23:28

Has anyone ever tried this. It's cheap and readily available.

In theory it should work quite well. The ring will be really well activated by the two chlorines.

I found this, but it only discussed making the mono nitrate.

niertap - 11-4-2012 at 23:33

Aromatic Nitration
By Kenneth Schofield

I also found this, apparently there may be some ipso substitution occuring. maybe someone else can get more out of the google book than I

Nicodem - 13-4-2012 at 11:09

Quote: Originally posted by niertap  
Has anyone ever tried this. It's cheap and readily available.

Yes, already in the year 1904.

In theory it should work quite well. The ring will be really well activated by the two chlorines.

Your knowledge of theory would certainly benefit from reading some chemistry books. The chlorine substituents are deactivating for the electrophilic aromatic substitution, so they don't activate that ring.

caterpillar - 13-4-2012 at 13:32

Nitration of polychlorobenzenes (but not 1,4- 1,3 and 1, 3, 5) is used for preparation of DATB and TATB and requires hard conditions- oleum, hi temperature and long time. The best of derivatives of benzene (for nitration, of course) is phenol of course.

AndersHoveland - 15-4-2012 at 14:14


Nitration of Chlorobenzene
90 mL of chlorobenzene is added dropwise with a dropper pipet or buret to a previously prepared, and cooled to room temperature, mixture of 110 mL of 99% nitric acid and 185 mL of 99% sulfuric acid, in a 1000-mL beaker, while the mixture is stirred mechanically with a magnetic stirrer. A stirrer is essential for the length of time required, you may try this by hand with a stirring rod at your own risk. The temperature will rise because of the heat of the reaction, but should not be allowed to go above 50-55 °C. After all the chlorobenzene has been added, the temperature is slowly raised to 95 °C and is kept there for 2 hours longer while the stirring is continued. An upper layer of light yellow liquid solidifies when cold. The layer is removed, broken up under water, and rinsed. The spent acid, on dilution with water, will precipitate an additional quantity of dinitrochlorobenzene. All the product is brought together, washed with cold water, then several times with hot water while it is melted, and once more with cold water under which it is crushed. Finally, it is drained and allowed to dry at room temperature. The product, melting at about 50 °C, consists largely of 2,4-dinitrochlorobenzene, along with a small quantity of the 2,6-dinitro compound, m.p. 87-88 °C. The two substances are equally suitable for manufacture of other explosives or alone as an explosive. You will need a graduated cylinder for measuring liquids, and a thermometer to monitor the temperature.

Warning: Dinitrochloro benzene is extremely poisonous. Inhaling the vapors can be deadly, as the compound oxidizes hemogoblin in the blood to a form that cannot bind with oxygen, leading to ischemia. Skin contact causes severe rash, itchy burning sensation, and blistering, analogous to poison ivy.

Here is a graph which shows that the paradichlorobenzene is mostly consumed after 15 minutes using 12M (molar concentration) HNO3, at only 10 °C.

Substituting the Chlorine atoms with Amine groups

"Both 2- and 4-chloronitrobenzene react with anhydrous ammonia at 200 °C to form the corresponding nitroaniline, whereas 3-chloronitrobenzene did not react under these conditions."
In the presence of the iodide ion, dry NH3, dissolved in pure alcohol, reacts rapidly with 2- and 4-chloronitrobenzene at 100 °C. 1-chloro-2,4-dinitrobenzene reacted with alcoholic ammonia at room temperature.
V. A. Tarasevich, M. F. Rusak, A. B. Tereshko, and N. G. Kozlov, Zh. Obshch. Khim, 67, 457 (1997); Chem. Abstr., 128, 270275r (1998)


Starting with the crude product of nitration, treatment with saturated alcoholic ammonia at room temperature converts the 2,6-dinitro-1,4-dichlorobenzene fairly rapidly to 4-chloro-2,6-dinitro-aniline, melting at 145 °C, while the other isomers react more slowly. On evaporating the alcohol, dissolving the organic residue in benzene, and extracting the benzene solution with concentrated sulfuric acid the amine is dissolved in the acid and the unchanged isomers can be recovered from the benzene. The residue from the evaporation of the benzene is then dissolved in the saturated alcoholic ammonia and heated on a water-bath under a reflux condenser, ammonia being passed in from time to time to replace that lost by evaporation. Under these conditions the 2,3-dinitro-1,4-dichlorobenzene is converted into 3,6-dichloro-2-nitro-aniline, and after 24 hours the procedure described above is repeated. After the amino compound has been extracted by acid as before, evaporation of the benzene leaves the product melting at 119 °C. Holleman believed this compound to be 2,5-dinitro-1,4-dichlorobenzene, and confirmed his hypothesis by synthesizing it from p-dichloro-acetanilide and from p-chloro-aniline, the intermediate products being identified in each case.
“The Dinitro Derivitives of Para-dichlorobenzene”, Annie Louise Macleod, Marion C. Pfund, Mary L. Kilpatrick. (1922). Journal of the American Chemical Society, Volume 44, Issue 2

Other Ideas

2-nitroaniline is converted to benzofuroxan by treatment with sodium hypochlorite solution at 0°C.
2,4-dinitroanaline undergoes an unexpectedly complex reaction when treated in alkaline methanol solution at 50°C with aqueous sodium hypochlorite. The product is a “chloromethoxybenzofurazan oxide”, namely 1-chloro-3,4-furoxan-4-methoxy-benzene.
Green and Rowe, J. Chem. Soc., 101, 2452 (1912). and
“Furazan Oxides. An Unusual Type of Aromatic Substitution Reaction", Frank B. Mallory, Suzanne P. Varimbi (1963)

"Azobenzene is also produced when KMnO4, acts on aniline, or when aniline is oxidized in alkaline solution by hypochlorite."
Proceedings of the American Pharmaceutical Association ,Volume 58, p288

Substituting a Chlorine atom with Hydrazine

Synthesis for 2,4-dinitrophenyl-hydrazine
Thirty-five grams of hydrazine sulfate added to 125 cc. of hot water in a 400 cc. beaker and stirred during the addition of 85 g of potassium acetate (an adjusted ammount of sodium acetate may be used instead. sodium hydroxide may be also substitute, but use of this will reduce yield and give a poorer quality product). The mixture is boiled five minutes and then cooled to about 70°; 75 cc. of alcohol is added, and the solid is filtered with suction and washed with 75 cc. of hot alcohol. The filtered hydrazine solution is used in the next step. In a 1 Liter flask fitted with a stirrer and reflux condenser, 50.5 g. of technical 2,4-dinitrochlorobenzene is dissolved in 250 cc. of alcohol; the hydrazine solution is added, and the mixture is refluxed with stirring for an hour. Most of the product separates during the first ten minutes and much heat is generated at this time so the solution should be be cooled. The crystals are then filtered, washed once with 50 cc. of warm alcohol (60°) to remove unreacted organic halide and then with 50 cc. of hot water. The solid weighs 30 g. and has a melting point over a transition of 180–192°C, which is accompanied by evolution of gas from partial decomposition. This procedure gives crystals pure enough for general use. By distilling half the alcohol from the filtrate a less pure second crop is obtained; this is recrystallized from alcohal, preferably n-butyl alcohol (30 cc. per g.) or pyridine may be used instead. The total yield is 40–42g which is about an 85% yield.
Purgotti, Gazz. Italian Chemical Journal. 24 (I) 555, (1894). and
Allen, J. American Chemical Soc. 52, 2955 ,(1930)

Solutions of 2,4-dinitrophenyl-hydrazine are also used for analytical work in chemistry, where it is known as "Brady's reagent",4-Dinitrophenylhydrazine
The substance is an explosive, although not a sensitive one, and no doubt more explosive nitrate salts could be formed from this compound.

More of this type of chemistry was also discussed in this forum in the "Quinone to make Energetic Compound" thread, beginning in the last part of page 2 through page 3:

[Edited on 15-4-2012 by AndersHoveland]

AndersHoveland - 10-11-2012 at 12:42

One more thing, apparently the application of heat changes the outcome of the reaction:

In two remarkable instances Korner has observed the displacement of the NO 2 group by the NH 2 group by the action of ammonia on nitro-haloid derivatives. Thus when 3-dinitropara-dichlorobenzene, C6H2Cl2(NO2)2 , is heated with an alcoholic solution of ammonia to 150-160 C (302- 320 F), it is converted into a nitrodichloramidobenzene, C6H3Cl2.NO2.NH2 , the NO2 group being eliminated as ammonic nitrite, which then becomes resolved into nitrogen and water, thus :

C6H2Cl2(N02)2 + 2NH3 = C6H2Cl2N02NH2 + N 2