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Nick
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Chloroacetic acid...
Is making this as simple as bubbling chlorine through acetic acid?
Does anyone know of an exact synthesis for it?
I'm thinking of nitroethanonitrile...
Make (mono)chloroacetic acid, react this with ammonia to get ammonium chloroacetate, heat this to get chloroacetamide, dehydrate this further (heat
with H2SO4?) to get chloroethanonitrile, then react this with AgNO2 to get nitroethanonitrile.
One problem I can think of, is what solvent would dissolve AgNO2 and chloroethanonitrile?
The chloroacetamide would be much more water soluble since it can form hydrogen bonds, so this could be used instead to get nitroacetamide, which
should also be rather explosive.
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madscientist
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I'll share most of what my chemical dictionary has to say on the topic of chloroacetic acid (just what info is potentially useful).
chloroacetic acid (chloracetic acid; monochloroacetic acid) CH2ClCOOH.
Properties: Colorless to light-brownish crystals, very deliquescent and caustic to the skin.
Constants: Specific gravity: 1.370 (70C); crystallizing point, alpha form, 61.0-61.7C; gamma form, 50C. The commerical material melts at 61 to 63C;
boiling range 186 to 191C. Soluble in water, alcohol and ether.
Derivation: By the action of chlorine on acetic acid in the presence of acetic anhydride, phosphorous, or sulfur.
I'm assuming chloroethanonitrile is chloroacetonitrile. 
chloroacetonitrile (chloroethane nitrile) ClCH2CN
Properties: Specific gravity 1.2020-1.2035 (25/25C); refractive index 1.4210-1.4240 (n 25/D); soluble in hydrocarbons, alcohols; insoluble in
water.
silver nitrite AgNO2.
Properties: Small, yellow or grayish-yellow needles. Become gray on exposure to light. Contain 70% (approximately) silver. Decomposed by acids.
Soluble in (hot) water; insoluble in alcohol. Decomposes at 140C. Specific gravity 4.4.
Couldn't you use a mixture of water and alcohol as a solvent for both AgNO2 and ClCH2CN? It wouldn't dissolve either too well, but it would dissolve
them enough for the reaction to proceed at a reasonable rate, methinks.
And my final thoughts on this idea: I don't think using a nitrite for nucleophilic substitution to prepare a nitro compound will work. There is a
distinct difference between a nitro group and a nitrite group. If I remember correctly...
Nitrite (nitrogen has a valence of three)
--O--(N=O)
Nitro (nitrogen has a valence of five)
--N(=O)2
I weep at the sight of flaming acetic anhydride.
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Nick
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Chloroethanonitrile is chloroacetonitrile, if you want to use it's old name
Thanks for that info, and yes I think an alcohol/water mixture might work to some extent. NaNO2 might be more soluble in alcohol, so that could be
used instead.
Check out Megalomania's synth. of CH3NO2 - uses NaNO2 and chloroacetic acid. NS
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madscientist
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Whoops! I forgot about this! The NO2 group resonates between the nitro and the nitrite structure! Therefore using a nitrite for nucleophilic
substitution on a organic compound *would* work.
I weep at the sight of flaming acetic anhydride.
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PHILOU Zrealone
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Simply allow CH2Cl-NO2 to react with NaCN in a solvant like DMSO, Acetone, Acetonitrile!
Those solvants dissolve quite wel AgONO and are used in nitro synthesis; AgX is quite unsoluble in those.The main problem with AgONO is that the
reaction forms both nitrite ester and nitroderivative in 50/50 proportion!
O2N-CH2-CN is quite powerful and sensitive but is less interesting on safety and power than the binaries made on place like N2O4/CH3-CN and HNO3
conc/CH3-CN!
The best molecule to perform nitrofixation via AgONO is I-CH2-CN!
I think it can be done from CH2I2 and AgCN in equimolar amounts in the dark (both reactant are light sensitive); of course some dicyanometane will
form too!
PH Z
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Polverone
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Silver nitrite substitutes?
Are there any nitrites that can be used in place of silver's for the production of, say, nitromethane/nitroethane from alkyl halides? I suppose that
the silver can be recovered and re-processed, but I would prefer not to use expensive silver compounds in the first place.
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Polverone
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Whoops!
What a silly question. A couple minutes with Google answered it for me. All I need to do is react an alkali nitrite with alkyl halide in DMSO. No
problem. Yay! Now if I only had some distillation equipment I could start cranking out the nitromethane...
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PHILOU Zrealone
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Absolutely no problem to get nitromethane?
Why do you think nitromethane is made via chloracetic acid?
I can predict you malonic acid will give chloromalonic acid upon contact with Cl2 more readily than acetic acid and will work too to produce NM!
ClCH2-CO2H + AgNO2 --> O2N-CH2-CO2H + AgCl
alfa nitroacids readily decarboxylate upon water boiling what also iomerises the nitrite ester into the nitrocompound!
O2N-CH2-CO2H --> CH3-NO2 + CO2
ONO-CH2-CO2H --> O2N-CH2-CO2H
Then HO2C-CHCl-CO2H + AgNO2 --> CH3NO2 + 2CO2
If you were to use something different than chloracetic acid or chloromalonic acid, I suppose you would use CH3-Cl, CH3-Br or CH3-I (light sensitive);
but I remind you all those are gaseous products and the two last are quite expensive, toxic and more suited for the desired reaction!
LiNO2 is better than NaNO2 that is better than KNO2 that are often better than AgNO2!
DMSO is better than DMF that is better than aceton for such reactions.
PH Z
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Polverone
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monochloroacetic acid patents!
US1304108 mentions producing monochloroacetic acid from trichloroethylene by heating it with water and high-conc. H2SO4 to 150-200 degrees.
Alternatively, trichloroethylene vapor is passed into hot sulfuric acid (this sounds more palatable for those without pressure vessels).
Also, it says that "It is true that it has been proposed in the patent literature to make ethyl chloroacetate or monochloroacetic acid by
treating dichlorovinyl ether with water or alcohol. It is also known that dichlorovinyl ether is derived from trichloroethylene by the action of an
alkali or of sodium ethylate in alcoholic solution."
This two-stage reaction might be of interest to a chemist of limited means.
US1322898 (for some reason not on Espacenet, but on uspto.gov) is an even more interesting read in certain aspects. It asserts that up to an H2SO4
concentration of 90% or so, the trichloroethylene merely carries water away from the acid unchanged. This is in sharp contrast to
Ullmann's statement that TCE is hydrolyzed with 70% H2SO4, and may explain why I had so little luck producing monochloroacetic acid with somewhat
diluted H2SO4.
British patent 132042 is also supposed to be a process for producing monochloroacetic acid from TCE, but Espacenet appears not to have it.
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Theoretic
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Well the reaction of alkyl halides with alkali nitrites produces nitro AND nitrito compounds - according to Marvin.
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Geomancer
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Does anyone have more details on the direct reaction with chlorine? Is the S/P truly catalytic, or does it get somehow used up?
This compound isn't on my current road map, but I am curious as to how I would prepare it.
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unionised
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Chloroacetc acid reacts with ammonia to give amino acetic acid (AKA glycine).
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fritz
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I don´t know the mechanism of the chlorination with S. But if you use P it is chlorinated to PCl3/PCl5 wich react with HAc producing acetylchloride.
This reacts with new HAc forming Acetanhydride which is better chlorinated than HAc itself:
(CH3CO)2O +Cl2 -> ClCH2CO-O-COCH3 +HCl
ClCH2CO-O-COCH3 +HCl -> ClCH2COOH + CH3COCl
It´s also possible to chlorinate HAc with I2/PCl5/red P (ratio:150g/1,5g/7g/3g).
Here with the Iodine ICl is formed which is more reactive than Cl2 and chlorinates HAc directly. This reaction takes place faster and no light (espec.
UV) is needed to carry out the reaction.
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unionised
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I also don't know about the use of sulphur for that reaction but the point is that once the PCl5 has become H3PO4 it is used up. You need a
stoichiometric amount of it; it isn't a catalyst.
Sunlight is cheap and anyway, it hardly matters if the next step in the reaction scheme gives the wrong product.
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Geomancer
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Won't photochlorination give a mixture of products? And what do you mean by "the next step in the reaction scheme"?
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unionised
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Yes, it will give a mixture, but I suspect that the catalysed reaction would too.
The next step in the scheme is where it reacts with ammonia to give glycine rather than the chloroacetamide.
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Polverone
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seeking various articles
I would be very grateful if anyone here could retrieve the following article (available electronically, but I don't have access rights):
LXXII.—The use of alpha-beta-dichlorovinyl ethyl ether for the production of chloroacetates and acid chlorides
Holland Crompton, Paule Laure Vanderstichele, 691-693, J. Chem. Soc., Trans.,1920
I am also looking for patents, articles, or other sources detailing the alkali conversion of trichloroethylene to dichlorovinyl ethyl ether.
PGP Key and corresponding e-mail address
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Polverone
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chloroacetates and acid chlorides from TCE
I was able to retrieve the requested article on microfilm. Here's most of the article:
| Quote: | The production of ethyl chloroacetate, and eventually of choroacetic acid, by the action of water on aB (these should be alpha and beta, but I
don't recall how to make greek symbols)-dichlorovinyl ethyl ether has been the subject of a large number of patents. By using dry hydrogen
chloride in place of water, chloroacetyl chloride is obtained (<A
HREF="http://l2.espacenet.com/espacenet/bnsviewer?CY=ch&LG=en&DB=EPD&PN=DE222194&ID=DE++++222194A++I+">DE222194</A><
img src="./images/smilies/wink.gif" style="border:none" alt=";)" />, and Imbert found (<A
HREF="http://l2.espacenet.com/espacenet/bnsviewer?CY=ch&LG=en&DB=EPD&PN=DE212592&ID=DE++++212592A++I+">DE212592</A><
img src="./images/smilies/wink.gif" style="border:none" alt=";)" /> that dichlorovinyl ethyl ether and ethyl alcohol react, with the production of
ethyl chloroacetate and ethyl chloride.
We find that aB-dichlorovinyl ether enters into a large number of reactions of the above type. It is attacked, and usually with great readiness, when
heated with alcohols, phenols, or acids. Action is of two kinds:
CHCl:CCl-OEt + ROH ->
1) CH<sub>2</sub>Cl-CO<sub>2</sub>R + EtCl
2) CH<sub>2</sub>Cl-CO<sub>2</sub>Et + RCl
and it seems likely that an additive compounnd, CH<sub>2</sub>Cl-CCl(OEt)-OR, is first formed, which decomposes into the products 1 and 2.
Our experience is that alcohols give the products of both reactions, but that 1 predominates, except in the case of methyl alcohol. Phenols give the
products of 1 only, and usually in excellent yield. Acids react mainly in accordance with 2, the products being ethyl chloroacetate and an acid
chloride. The yields are variable, but it would appear that reactions of the above type could be used in certain cases for the production of
chloroacetates or acid chlorides.
To prepare aB-dichlorovinyl ether, sodium is dissolved in dry alcohol in sufficient quantity to form a saturated solution of sodium ethoxide.
Trichloroethylene is then added in the proportion of one molecule of trichloroethylene to one and a half atoms of sodium. Heat is applied until action
commences, when further heating is unnecessary. The product, when cold, is mixed with a large volume of distilled water, and the oil which separates
is washed, dried with calcium chloride, and rectified. The main portion distills at 122-126 degrees C, and this is nearly pure dichlorovinyl ethyl
ether. The yield is about 70 percent of the theoretical.
For the action on alcohols or phenols, the substance was employed in as dry a state as possible and mixed with the ether in equivalent quantity. Heat
was applied to start the reaction, but further heating was often unnecessary, except toward the end of the process. In other cases, however, head had
to be applied throughout to maintain the reaction. The products were separated by fractional distillation, or, where possible, by crystallization.
The results with methyl alcohol were not in accordance with Imbert's statement. Ethyl chloroacetate was the main product and methyl chloroacetate
was only produced in relatively small quantity. Ethyl alcohol gave the expected excellent yield of ethyl chloroacetate. iso-Amyl, heptyl, allyl, and
menthyl alcohols were each found to yield the chloroacetate of the acid radicle, but ethyl chloroacetate was also formed in these cases.
All the phenols examined gave good yields of the aryl chloroacetate, but in no case was ethyl chloroacetate detected. The compounds dealt with were
phenol, o-cresol, guaiacol, alpha and beta-naphthol, resorcinol, and quinol. The two latter compounds gave the bischloroacetates.
The monobasic acids, the behavior of which with dichlorovinyl ethyl ether was examined, were acetic, chloroacetic, phenylacetic, benzoic, anisic, and
alpha-naphthoic. In most cases action occurred readily on heating, but it was necessary to apply heat continuously throughout the process. Some
hydrogen chloride was evolved in each case, but ethyl chloride was only observed in the case of anisic acid and of naphthoic acid. Ethyl chloroacetate
was always present as the chief product of the reaction. The acid chloride formed at the same time was isolated in a pure state in the reactions with
acetic, chloroacetic, and benzoic acids. In the other cases, the acid chloride was not obtained pure, but its presence was indicated by the immediate
production of the corresponding amide on treating the appropriate fraction with ammonia. |
Oooh, making acetyl chloride and ethyl chloroacetate - what interesting products to obtain from a cheap solvent chemical! Now if only sodium ethoxide
were a little easier for an amateur of limited means to prepare in a clean and concentrated state.
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vulture
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Sodiummethoxide can be prepared from sodiumamalgam and methanol.
Sodiumamalgam is available through electrolysis of Na-salts with Hg elektrode...
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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clnt
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Nitromethane from chloroacetate and nitrite
Do any of you know where I could find reaction rate constants and orders for the reaction of sodium chloroacetate with sodium nitrite
(to make nitromethane) which you have been talking about?
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jack-sparrow
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Chloroacetyl chloride can be made by reaction of acetyl chloride with 1 equivalent of N-chlorosuccinimide in dichloromethane at reflux for 3 weeks.
Then hydrolysis with water leads to chloroacetic acid.
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The_Davster
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Could trichloro-s-triazinetrione could be used instead of NCS? The reaction seems pretty nice and this would make it more OTC. A three week reflux
time does seem too long for practical though .
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jack-sparrow
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Maybe, I know that this reagent (also know as isocyanuric chloride or trichloroisocyanuric acid) is in vogue these days. The reflux time is long
because of the very low solubility of NCS in dichlormethane
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kazaa81
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I've tried some time ago to synthetize monochloroacetic acid, by bubbling trieline into conc. sulphuric acid.
I've read somewhere that this is a good way to obtain pure monochloroacetic acid.
Unfortunately, due to not suitable hardware (plastic tubes!), my synthesis failed...
If someone can try this out, we will all thank him/her.
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kazaa81
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Trieline [1,1,2-trichloroethene]
C2HCl3
CAS #: 79-01-6
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