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Rosco Bodine
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Attached is a simple method for purification to reagent grade
of the technical grade m-nitrobenzene from the nitration above .
Attachment: US1665005 alkali purification of m-dinitrobenzene.pdf (201kB)
This file has been downloaded 822 times
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Rosco Bodine
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another sulfide reduction reagent
Earlier a patent , US1689014 , was posted concerning the use of ferrous sulfide produced in situ from addition of sodium sulfide or sodium polysulfide
to a solution of ferrous sulfate , as a selective reducing reagent for nitroaromatic compounds .
A similar later patent has been found describing the analogous usefulness also for manganous sulfide , produced the same way as described in the
earlier patent for the ferrous compound .
US1765660
[Edited on 24-1-2007 by Rosco Bodine]
Attachment: US1765660 Manganous Sulfide reduction of nitroaromatics.pdf (94kB)
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Rosco Bodine
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Mood: analytical
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2,4-dinitroaniline
Here is a synthetic method for 2,4-dinitroaniline via dinitrochlorobenzene reacted with urea.
Recently I have suggested in the tetrazole thread a possible usefulness for the 2,4-dinitrobenzene diazonium perchlorate in combination or mixture
with other energetic perchlorates.
Attachment: US1752998 2,4-dinitroaniline via 2,4-dinitrochlorobenzene plus urea.pdf (66kB)
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AndersHoveland
Hazard to Other Members, due to repeated speculation and posting of untested highly dangerous procedures!
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3-nitroanaline, nitrous acid with aniline
The 3-nitroaniline is an important precursor for the preparation of diazoperchlorate-3-nitroaniline.
NO2—C6H4—N[+]ΞN ClO4[-]
From 3-chloronitrobenzene
Apparently, 3-chloronitrobenzene can be prepared by the electrophilic chlorination of nitrobenzene with chlorine in the presence of ferric chloride
FeCl3.
Varnholt, J. prakt. Chem. (2) 36, 25 (1887).
The reaction was also mentioned in another forum
http://www.thenakedscientists.com/forum/index.php?topic=1844...
Unfortunately, nitration of chlorobenzene does not result in 3-nitroaniline.
Both 2- and 4-chloronitrobenzene react with anhydrous ammonia at 200degC to form the corresponding nitroaniline, whereas 3-chloronitrobenzene did not
react under these conditions.
V. A. Tarasevich, M. F. Rusak, A. B. Tereshko, and N. G. Kozlov, Zh. Obshch. Khim. 67, 671 (1997); Chem. Abstr. 128, 2701275r (1998)
In the presence of the iodide ion, dry NH3, dissolved in pure alcohol, reacts rapidly with 2- and 4-chloronitrobenzene at 100degC.
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)
So basically, nitrobenzene would have to halogenated with bromine in the presence of ferric bromide FeBr3 (in the absence of water obviously) to
3-bromonitrobenzene, which could then be reacted with anhydrous ammonia at room temperature to form 3-nitroaniline, since bromine substitutes off much
more easily.
for readers without knowledge of organic terminology, the different structures of the isomers of nitroanaline can be seen:
https://7007983270460794965-a-1802744773732722657-s-sites.go...
Nitration of Aniline
Nitration of analine with the usual mixture of concentrated nitric/sulfuric acids is very problematic, because of both charring, and oxidation of the
analine to nitrobenzene
(using a large excess of sulfuric acid helps minimize formation of nitrobenzene). It is true, however, that low yields of 3-nitroanaline (without
significant formation of other isomers) can be obtained, however. Even the use of 60% nitric acid can result in some charring of analine, and this can
be partially reduced by cooling the nitration bath. With 75% concentrated nitric acid added to excess analine, charring takes place fairly quickly.
Adding an acetyl group to the analine, using acetic anhydride, before nitration will make the reaction run much smoother without the byproducts, the
acetyl group later being hydrolyzed off with a mildly strong base, but in this case mostly 4-nitroanaline is produced, with some lesser formation of
2-nitroanaline.
Reaction of Nitrous Acid (HNO2) with Aniline
Nitrous acid (NaNO2 and acid) can be used to nitrate phenol or analine. If concentrated mineral acids are present with the nitrous acid, mostly the
para-nitro will be produced (91% yield), but if glacial acetic acid (concentrated) is present with the nitrous acid, yields of 74% ortho-nitro are
possible. Ortho means the nitro is in the 2-position, adjacent to whatever other group is on the ring. Para means the nitro is on the opposite end of
the ring from the other group.
The theory is that a nitrosyl ion (NO+) initially nitrates the ring, and then the resulting nitroso group gets oxidized to a nitro. ("Aromatic
nitration", K. Schofield. 1980)
However, this nitrosyl ion equilibrium with nitrous acid is only present under strongly acidic conditions, certainly not when nitrous acid is in an
alkaline envirorment., where it is mostly in the form of nitrite.
One source mentions that reaction of analine with nitrosonium hydrogen sulfate NO[+] [-]SO4H produces nitrobenzenediazonium salts.
NO2C6H4–N[+]ΞN
First, the nitro group is added to the analine. It is only after the acids have been somewhat diluted with water that the amino group can be
diazotized, as diazotization cannot take place in extremely concentrated sulfuric acid.
"Interaction of Analine with diazotizing and nitrating Agents in Concentrated sulfuric Acid"
Mikhail V. Gorelik, Vera I. Lomzakova, Elena A. Khamidova
Research Institute of Organic Intermediates and Dyes, Moscow, Russian Federation
nitrosonium hydrogen sulfate is the same thing as nitrosyl sulfuric acid, which may be prepared by bubbling mixed nitric oxide/nitrogen dioxide gases
into concentrated sulfuric acid.
(3)H2SO4 + NO2 + NO --> (2)NO[+]SO4H[-] + H3O[+]SO4H[-]
Whereas 3-nitroanaline can be easily diazotized with dilute nitrous acid, both 2-nitroanaline and 3,5-dinitroanaline require moderately concentrated
sulfuric acid to be present, for formation of nitrosonium ions.
Treatment of a 1:1 ratio of nitrosylsulfuric acid to analine, using 92.5% concentrated sulfuric acid, leads to formation of about three times as much
4-nitrodiazonium salt as 3-nitrodiazonium salt. Using 95.5% sulfuric acid leads to a 6 to 4 ratio of the isomers, while 100% concentration leads to
equal formation of both. The treatment of previously prepared benzenediazonium salt with nitric acid does add any nitro group.
you can see a bottle of nitrosylsulfuric acid:
https://7007983270460794965-a-1802744773732722657-s-sites.go...
[Edited on 29-7-2011 by AndersHoveland]
I'm not saying let's go kill all the stupid people...I'm just saying lets remove all the warning labels and let the problem sort itself out.
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AndersHoveland
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Nitration of aniline unexpectedly gives 47% yields of meta-nitroaniline (with nitro group in the 3-position). This is because analine under acidic
conditions forms the anilinium ion,
C6H5NH3[+], which is meta-directing towards the addition of the nitro group.
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