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Author: Subject: Oxydation of Ethylamine into Nitroethane?
akinmad
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shocked.gif posted on 26-8-2003 at 15:54
Oxydation of Ethylamine into Nitroethane?


Dear Friends,

Maybe some of you shall laugh at my ignorance regarding the assumption made in the topic. But I wonder if it is possible to oxidize Ethylamine into Nitroethane?

Rgrds,:):):)




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Nick F
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[*] posted on 27-8-2003 at 04:07


Oxidising -NH2 to -NO2 is certainly possible (usually with acidified MnO4- or peroxyacids I believe), but I doubt it will work on everything. Tertiary amines will normally do it, I have heard of cubane and adamantane amines being oxidised to nitro's, but I'm not sure about primary aliphatic amines like you suggest...
But I am really not very knowledgable in this area at all, maybe someone else could give you some more useful info...

Edit: you should check out the Hive / Rhodium's webpage, they should have a load of nitroethane synths...

[Edited on 27-8-2003 by Nick F]
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[*] posted on 27-8-2003 at 22:04


Here, I'm feeling generous tonight.

http://www.rhodium.ws/chemistry/nitroethane.html

Its method 8
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Mendeleev
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[*] posted on 7-12-2004 at 10:38


That link above which no longer works, gave a procedure which used ethyl bromide and potassium nitrite. I like this procedure but it requires about 600 mL of either DMF or DMSO to get 10-20 grams of product, which is freakin' absurd considering DMSO and DMF cost 3 times more than typical solvents like toluene or chloroform. Is it possible to use a different solvent, or to do it without the solvent altogether? Or at least reduce the amount of solvent used by about 6 times?



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[*] posted on 7-12-2004 at 11:01
Ref: Synthesis of Nitroethane


This method was translated using Babel web translator from Zelot's web page......
http://ssb.h1.ru/chemic.htm

where there is much info on other synthesis from the Hive and rhodium's as well as from excellent russian chemists......solo
Quote:

Nitroethane from ethyl sulfate of sodium


Regards.

> 1) (from foxy2) intermixing with komn. rate.
> sulfuric ktu, ethyl alcohol and waterless sulfate
> sodium. Optimum proportions and time are unknown,

Obtained thus ethylsulfuric acid and then ethyl sulfate. Came out mixture with sulfate approximately 50 to 50. Nitroethane 28% (along ethyl sulfate) left this mixture!
So here, sodium ethyl sulfate has melting point lower than y00S. It did not earlier note this 4. But indeed this is important, indeed it turns out that the reaction with nitrite occurs in the fusion!
Apparently my failures earlier were connected with poor ethyl sulfate.

> 2) (US 3,024,263 - courtesy of PolytheneSam)
> to boil alcohol with two equivalents of hydrosulfate
> sodium

Kha! Read a little an example which in their patent. Can 4 something it did not understand, but they propose to mix up 113g and 20g (~2'ml) ethanol. Then this must be boiled on the bath, cooled and filtered out. As to make this, if hydrosulfate completely absorbs alcohol, simply it becomes somewhat wetter how it was.
Another matter if there misprint, and alcohol is necessary, well let us say 120 or this 200g. already actually, but it is then necessary to drive off the surplus of alcohol on the water bath. So here entire alcohol is not driven off on the bath, it is how much not Grey. As a result nevertheless the mixture of ethylsulfuric with alcohol is obtained.
Certainly obtaining this etilul'fata it does not prevent, but with this patent everything after all something not thus.

Yes, he forgot to say, in spite of all these neuvyazochki ethylsulfuric everything after all is obtained (I was taken y00ml of alcohol to 113g hydrosulfates of sodium). Output ~77% (on hydrosulfate), the part of ethylsulfuric acid is driven off together with alcohol, so that is actual output more. (50 shrewd to the washing) conversely returned 90ml. of rest it flew away from yshch0ml of alcohol used, it remained on filtered sulfate and as admixture to the ethylsulfuric acid...

it is beaten




How do you do, comrade!

Outstanding work!

It is pleasant to feel elbow, Vitsh. To you, I hope, also.

Listen to, two completely practical questions:

1) describe in the details the method of neutralization with ethylsulfuric, tomcat you used.

2) describe to me, tuparyu, as you dehydrate from the final liquor!! But that in someone, whom I know and love, with this of problem. In the details, if it is possible. Under the fact that melting point ethyl of sulfate of less than hundred you do have in the form that he on the steam bath how slightly liquid? How you did determine that entire water was shrewd?

But here is another pair of observations from my friend NEKOZLYU, which it sent to me by the pigeon mail:

"4, by the way, protupil. In reality in the method and lya Foksi2 _ _ is always obtained clean ethylmethylsulfuric kta. And not khera of no hydrosulfate, no dissolved sodium sulfate. Sulfate ion appears precisely in the process of hydrolysis - whereas indeed for that is necessary dehydration, indeed faken of ekvilibrium! This grebanaya kta is decomposed by water! It is shorter the less the water in the process of neutralization, those better, and since it there any differently is formed, losses are inevitable. Key to the success - always the surplus of alkali, a good mixing and the dropping funnel.
My best result - with slightly moistened theoretically calculated sodium bicarbonate in the icy bath and _ by a good _ mixing (meshalochka it is made from the nekollektornogo (nonsparking) little motor from the old bobbin tape recorder:) - gave out the mixture, which consists of _ metil_sul'fata to 70%. 4 it was used to the methylation of hydroquinone - well, until without the commentaries, it is necessary to repeat - I will say only that in principle it works.
One additional time, latter, left about 60% - was used the nasyshchenyy solution Of naON in the icy bath. The reason for this, is thought to me, in the fact that one time I allowed mixture to become acidic, although in all to the pair of minutes. It feared to pereshchelochit', whereas entire time of the standards of rN. but not you will every 30 s. there papers thrust. Only then it reached me, that EVER it cannot be to it made it possible to be acid.
This is what occurs. As soon as in the mixture appears free alkyl sulfuric kta, it will be hydrolized alcohol and to sernyagu. However, afore-mentioned - no longer one, but two- basic kta. It is connected with two molecules of alkylsulfate and thus it generates the already TWO molecules of alkyl sulfuric. From them are obtained already four molecules and, etc. - i.e., reaction occurs avalanche-type, in the geometric progression. It is shorter, IT IS NOT POSSIBLE to lower rN of lower than seven.
But I used here what method for determining the content of sulfate ion. Weighed sempl of the received salt - from 1 to 5 grams, r -r4l in the minimum of hot water was mixed up with the surplus of nasyshchenogo chloride calcium. Sediment filtered, it washed in hot water, dryers again it weighed. The molar mass of monohydrate of sodium sulfate (here only 4 it is not confident, what at hundred degrees it forms precisely monohydrate - who knows accurately?) the same as monohydrate of calcium S- 3s-o-cetyre -four, so that, speaking in general terms, immediately it is possible to obtain percent relationship. I want to note that this procedure in reality is in no way long and is not haemorrhoidal, although appears the same.
Methyl sulfate of sodium - pleasant sky with the weak smell of gouache, to the taste it is slightly similar to the olives, in the period of the quasi-electromagnetic instability of solar radiation during irradiation by gamma-rays with the frequency of range... "
On this pigeon message slightly is interrupted, yes even generally, there was this pigeon, it is accurately unknown - it remained from it entirely insufficiently in order to determine.

Again thanks, Vitsh, for your pervootkryvatel'skiye experiments, now we will know that it is possible entire this calcium khuynyu to boldly skipnut'. To small still podshlifovat' detail - you will answer, yes NEKOZLYU within the next few days will try type nitromethane, and there also dispatch boldly can be will be written into the metropole.

MoonLight




Zdarova!

> 1) describe in the details the method of neutralization with ethylsulfuric,
> tomcat. you used.

I added the saturated solution Na2ccO3 to the ethylsulfuric, during the active mixing. But pochitav this letter it understood, why it left only 50%. I proved to be not as clever as To nekozlyu;) .
I calculated the content of ethyl sulfate according to a quantity of spent carbonate (sulfuric dibasic in contrast to the ethylsulfuric).

> 2) describe to me, tuparyu, as you dehydrate from
> final liquor!! But that in someone, whom I know and
> I love, with this of problem. In the details, if it is possible.

It steamed in the plate on the steam bath with the blowout from the foehn, stirring slowly in order to destroy crust. When it began to thicken, then blowout removed so that it would not blow away the salt from the plate. It heated somewhere half-hour still and it left in the exsiccator on day.
Such an ethyl sulfate does not adhere with the grinding in the coffee mill, but it is converted into the dust.

> under the fact that melting point ethyl of sulfate of less than hundred you have in
> to form, that it on the steam bath how slightly liquid?

Tochno-tochno. But this yet not all. After obtaining of nitroethane the remainder in the flask was downy as the thickening foam. But the past times - sintered piece.

it is beaten




Zdarova!

> this grebanaya
> kta is decomposed by water!
> is shorter than it is less water in
> the process of neutralization, those better, and since it there
> any differently is formed, then losses are inevitable. Key k
> to success - always the surplus of alkali, the good mixing
> and the dropping funnel.
> my best result - with that slightly moistened
> by theoretically calculated sodium bicarbonate in the the icy
> to bath and _ good _ mixing (meshalochka is made from
> nekollektornogo (nonsparking) little motor from the the old
> the bobbin tape recorder:) - gave out the mixture, which consists of
> _ metil_sul'fata to 70%. 4 it was used on
> the methylation of hydroquinone - well, thus far without the commentaries,
> it is necessary to repeat - I will say only that in principle it works.
> one additional time, the latter, left about 60% -
> was used the nasyshchenyy solution Of naON in the icy bath.
> the reason for this, it is thought to me, in the fact that one time 4
> allowed mixture to become acidic, although in all to the pair
> minutes. It feared to pereshchelochit', entire time of the standards of rN. but not
however, > you will every 30 s. there papers thrust. Only
> then me reached, that EVER it cannot be to it allowed
> to be acid.

It made ethylsulfuric acid with sodium carbonate, adding acid to the alkali. Result also, as during the addition of alkali to the acid, nevertheless came out mixture with sulfate. Output of nitroethane from this mixture ~15%.

I think that there is no difference that to what to add, here and in the procedure of obtaining pyrocatechol is added alkali to the acid.

it is beaten

PS: by the way, there is suspicion, that ethyl sulfate of sodium is melted all after all at a higher temperature, and here its monohydrate (it read somewhere on khayve, that it is formed monohydrate) is melted below y00S. It seems that the reaction occurs more easily with monohydrate, so that to finish drying it is final everything after all not must.




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[*] posted on 7-12-2004 at 13:59


Search for DMDO i belive it is, its a ketone peroxide of some sort, simple and high yeilding.



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Mendeleev
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[*] posted on 7-12-2004 at 14:00


I was aware of the ethyl sulfate procedure, but it is rather low yielding, both the synthesis of nitroethane and the synthesis of diethyl sulfate and sodium ethyl sulfate, unless one uses oleum, which I am not inclined to do. In my opinion ut of the 18 methods outlined on rhodium, two are very easy and decent yielding: the oxidation of ethylamine by potassium permanganate, but monoethylamine is somewhat of a tricky precursor to synthesize. However ethyl bromide + KNO2 is as easy as it gets, just mix and stir in a beaker, the only other thing need is either DMF or DMSO. It says ethylene glycol can be used, but it gives side reactions. So what I'm wondering is for the given reaction with 32.5 g ethyl bromide and 36 g KNO2, would you be able to use say 200-300 mL solvent instead of 600 mL? Last thing, about the ethylene glycol, how badly would the yield suffer, and would you be able to use the green antifreeze shit?

[Edited on 7-12-2004 by Mendeleev]




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Darkfire
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[*] posted on 7-12-2004 at 14:21


Yuor gonna want clear stuff, you can distill it it, or just get clean clear anti-freezee, thats what i got. DMSO is cheap and easy to get, look in alteritive medicine places, i find it at a place called "Farmers Market." Dotn mess around with impure shit, its more trouble than its worth.



\"I love being alive and will be the best man I possibly can. I will take love wherever I find it and offer it to everyone who will take it. I will seek knowledge from those wiser and teach those who wish to learn from me.\" Duane Allman
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[*] posted on 18-12-2004 at 05:06


Quote:
Originally posted by MendeleevSo what I'm wondering is for the given reaction with 32.5 g ethyl bromide and 36 g KNO2, would you be able to use say 200-300 mL solvent instead of 600 mL?
[Edited on 7-12-2004 by Mendeleev]


I think it could even be a better idea to use less DMF/DMSO as this is a simple Sn2 that shouldn't give rise to much side-products. Since: Rate = k[EtBr][NO2-], the higher concentrations of both reactants should speed up the reaction, to achieve higher concentrations, use not much more DMF/DMSO than it is enough to dissolve your reactants... Also, add catalytic amount of KI to the mix to speed up the reaction.

[Edited on 18-12-2004 by Sociopath]
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Marvin
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[*] posted on 18-12-2004 at 06:01


KNO2 is not very soluable in organic solvents, though DMSO is better than DMF. I do not think more solvent would be in a writeup than optimum for the reaction. AgNO2 is more soluable, one of the reasons the reactions go to higher yeilds.

Side reactions include the production of alkyl nitrites which tend to build up in the reaction mixture and react with produced nitro compounds. This reduces yeild and controling this is critical to success with KNO2.
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Mendeleev
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[*] posted on 18-12-2004 at 09:15


Ethyl nitrite boils at 17 C so perhaps heating the reaction mixture will avoid this problem, and maybe even speed the reaction up.
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Marvin
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[*] posted on 18-12-2004 at 20:21


Mendeleev, do you honestly think thoughts like that failed to occur to the people that designed the method?

Do you honestly think they didnt vary the temperature, the reaction conditions, the concentration to try and make it better before they published?

Read more, guess less. Do an experiment exactly how its supposed to be done the first time, *then* vary things.
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Mendeleev
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[*] posted on 18-12-2004 at 23:42


I have read every source available to me, I'm sorry if I offended you with my guessing, no harm intended. I may carry out this experiment in the futre.
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[*] posted on 5-3-2005 at 05:46


An idea put to me was:
a) condensation of acetaldehyde with hydroxylamine
CH3.CHO + H2NOH -> CH3.CH=NOH
b) followed by reduction of the double bond -> CH3.CH2-NHOH
c) finished off with oxidation to nitroethane. (possibly with KMnO4).

I've not done it but it looks good to me, in that everything 'should' work.
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[*] posted on 6-3-2005 at 03:54


If so, why would you need to reduce if the intermediate thus produced is already partially oxidized? :D

sparky (^_^)

P.S. Nitroso compounds are only a tautomerization away from oximes. At least for aliphatic ones.

[Edited on 6-3-2005 by sparkgap]




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[*] posted on 7-3-2005 at 02:09


Hah, I'll just smash my head against this brick wall here. That might knock some sense into it.

It would be kind if anyone can find any useful articles which they may have on their hard disk. There's a list below. I don't have access to a library right now. Here are the entries for the Oxidation of oxime to nitro (from J. March, 4e).

Jerry March - Advanced Organic Chemistry, 4e page 1199

Oxidation of Primary Amines, Oximes, Azides, Isocyanates, or Nitroso Compounds to Nitro Compounds

R3CNH2 --> R3CNO2 (using KMnO4)

R2C=NOH --> R2CHNO2 (using F3CCOOOH)

Tertiary alkyl primary amines can be oxidized to nitro compounds in excellent yields with KMnO4.[ref 398] This type of nitro compound is not easily prepared in other ways. All classes of primary amine (including primary, secondary, and tertiary alkyl as well as aryl) are oxidized to nitro compounds in high yields with dimethyldioxirane.[ref 399] Other reagents that oxidize various types of primary amines to nitro compounds are dry ozone,[ref 400] various peracids,[ref 401] including peracetic and peroxytrifluoroacetic acids, t-butyl hydroperoxide in the presence of certain molybdenum and vanadium compounds,[ref 402] F2-H2O-MeCN,[ref 402a] and sodium perborate.[ref 403]
Dimethyldioxirane in wet acetone oxidizes isocyanates to nitro compounds (RNCO --> RNO2).[ref 404] Oximes can be oxidized to nitro compounds with peroxytrifluoroacetic acid, among other ways.[ref 398] Primary and secondary alkyl azides have been converted to nitro compounds by treatment with Ph3P followed by ozone.[ref 405] Aromatic nitroso compounds are easily oxidized to nitro compounds by many oxidizing agents.[ref 406]
OS III, 334; V, 367, 845; VI, 803.

396 Murray; Singh Synth. Commun. 1989,19, 3509. This reagent also oxidizes primary amines to hydroxylamines: Wittman; Halcomb; Danishefsky J. Org. Chem. 1990, 55, 1981.
397 Biloski; Ganem Synthesis 1983, 537.
398 Larson, in Feuer The Chemistry of the Nitro and Nitroso Groups, vol. 1; Wiley: New York, 1969, pp. 306-310. See also Barnes; Patterson J. Org. Chem. 1976, 41, 733. For reviews of oxidations of nitrogen compounds, see Butler Chem. Rev. 1984, 84, 249-276; Boyer Chem. Rev. 1980, 80, 495-561.
399 Murray; Rajadhyaksha; Mohan J. Org. Chem. 1989, 54, 5783. See also Zabrowski; Moorman; Beck Tetrahedron Lett. 1988, 29, 4501.
400 Keinan; Mazur J. Org. Chem. 1977, 42 844; Bachman; Strawn J. Org. Chem. 1968, 33, 313.
401 Emmons J. Am. Chem. Soc. 1957, 79, 5528; Gilbert; Borden J. Org. Chem. 1979, 44, 659.
402 Howe; Hiatt J. Org. Chem. 1970, 35, 4007. See also Nielsen; Atkins; Norris; Coon; Sitzmann J. Org. Chem. 1980, 45, 2341.
402a Kol; Rozen J. Chem. Soc, Chem. Commun. 1991, 567.
403 McKillop; Tarbin Tetrahedron 1987, 43, 1753.
404 Eaton; Wicks J. Org. Chem. 1988, 53, 5353.
405 Corey; Samuelsson; Luzzio J. Am. Chem. Soc. 1984, 106, 3682.
406 See Boyer, in Feuer, Ref. 398, pp. 264-265.
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[*] posted on 7-3-2005 at 15:06
Oximes to nitroalkanes


When searching for articles on the oxidation of oximes to nitroalkanes yesterday I found a very useful paper.
In Synthetic Communications, 28(24), 4531-4535 (1998), oximes are oxidised to nitroalkanes in good yield using only oxone in aqueous acetone-acetonitrile at pH 7.5. Primary, secondary and benzylic oximes all give nitroalkanes in good (generally 60-70%) yield. The closest substrate to acetaldehyde oxime is the oxime of hexanal, giving 1-nitrohexane in 70% yield. The only problem I forsee for the production of nitroethane is its low boiling point, similar to that of acetonitrile. Best will probably be to follow the extraction of the mixture with a low-boiling point solvent (e.g. ether as in the paper) by several water washes to remove any residual acetonitrile. The general procedure is as follows (apologies for not uploading the entire article):

General Procedure
A freshly prepared solution of oxone (11.7 g, 19.0 mmol) in 23 ml of water and aqueous acetone solution (20 ml) was added simultaneously to a vigorously stirred mixture of oxime (0.52 g, 3.8 mmol), acetonitrile (5 ml) and aq. phosphate buffer (pH 7.5, 0.05 M) in water (20 ml) was stirred at 45C for the specified time (Table). The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was cooled to room temperature, the product extracted into ether (2x25 ml), washed with saturated brine, dried (Na2SO4) and the solvent removed in vacuo to afford the crude product which was purified through a silica gel column eluted with chloroform-pentane (1:4).

The time for the oxidation of hexanal oxime to 1-nitrohexane is 6 hours. All reactions were complete in 10 hours. To make the procedure more home-chemist friendly, the column chromatography should be skipped and instead a distillation of the crude nitroethane carried out.

The above procedure is the most OTC by far for this oxidation. The only real alternative seems to be the use of peroxytrifluoroacetic acid, as mentioned by CherrieBaby. But anyone with access to trifluoroacetic acid would surely not waster their time making nitroethane. Still, I can retrieve the article if anyone is interested. I'll also have a look at some of the other articles listed. The DMDO, peracetic acid and sodium perborate oxidations of amines may be interesting, though I think the latter seems to only work on aromatic amines. This is according to reference 403, which I happened to read yesterday for an unrelated purpose: the sodium perborate-AcOH promoted Baeyer-Villiger oxidation of acetophenones to phenyl acetates is reported in the same article.
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[*] posted on 8-3-2005 at 00:16


Kinetic. could you please upload the article if at all possible. The proceedure seems very useful.
(I'm curious to what the table has)



Great find by the way.
Oxone does amazing stuff.

[Edited on 8-3-2005 by enima]
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[*] posted on 8-3-2005 at 02:46


As already briefly mentioned by Kinetic, there is also another efficient OTC oxime-to-nitro oxidant, for those of us who can't get Oxone. Sodium perborate in acetic acid oxidizes oximes of many types into their nitro counterparts. Like usually happens when I search for something in the mess of my files I couldn’t find the paper but I think the reference (found in another paper) is Synlett (1992) 337. I remember that the method worked on aliphatic oximes as well.

Anyway, what’s maybe new and more important, pyruvic acid oxime should be as useful (or even more) as a substrate to be oxidized to nitroethane. Pyruvic acid is much more accessible than acetaldehyde or its trimer. It can be made by pyrolisis of tartaric acid in the presence of H2SO4 (a glycol rearrangement to HOOC-CH2-CO-COOH, followed by decarboxylation to Me-CO-COOH). I see no special reason why the perborate oxidation would not work on Me-C(=NOH)-COOH just as it works on other oximes. The beauty is that both the oxime formation and its oxidation can probably be made in one pot. The intermediate 2-nitropropionic acid easily decarboxylates to nitroethane. So you already get your favorite product at the end. Off course, pyruvic acid must be used as an alkali salt in order to form hydroxylamine from H2NOH hydrochloride or sulphate. Alternatively sodium acetate can be used as a base. Luckily calcium pyruvate can be bought online if you look hard enough on the net, so for some there is even no need to make pyruvic acid at all. The reactions involved would be:

Ca(MeCOCOO)2 + 2NH2OH×HCl =[AcOH]=> CaCl2 + 2H2O + 2Me-C(=NOH)-COOH
Me-C(=NOH)-COOH + NaBO3×4H2O =[AcOH]=> Me-CH(NO2)-COONa + H3BO3 + 3H2O
Me-CH(NO2)-COONa + HCl =[AcOH]=> Et-NO2 + CO2

Unfortunately I never was so desperate to try the reaction myself (who needs nitroethane anyway ;) ), but if I would I would do it like this:
I would dissolve the calcium pyruvate in acetic acid solvent and add two equivalents of hydroxylamine hydrochloride. I would then let it reflux for a few hours in order to assure the conversion to the oxime, then add the sodium perborate and continue the reaction by the instructions from the paper (which I can’t find at the moment). At the end I would however add as much of conc. HCl as it is needed to acidify the reaction and continue the reflux for one hour more (a 20% excess in relation to sodium perborate should do). This is because 2-nitro-propionic acid is a considerably stronger acid than acetic acid and is therefore mostly deprotonated due to the formed borate being basic. Its deprotonation would inhibit the decarboxylation step, so the addition of HCl is in order to assure all of the acid decarboxylate to the nitroethane. The work up should be a simple dilution with cold water, separation of the EtNO2 layer (extraction with CH2Cl2 or ether is also advisable), washing with water, NaHCO3, brine and distillation.
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[*] posted on 8-3-2005 at 14:18


Oxidation of ethanol to the aldehyde maybe?

Not sure how well this would work but recently vanadium pentoxide has been found to effectively oxidize alcohols to aldehydes. It gives very nice high yields on benzyl chloride and substited benzyl chlorides.

S. Velusamy, T. Punniyamurthy, Org. Lett., 2004, 6, 217-219.

For 1-heptanol the yield is 43% post GC.
Ethanol is cheap and the vanadium is used as a catalyst at 5% molar ratio to the alcohol. Even if the proceedure is low yielding it would still be possible to produce acetylaldehyde.

I wonder how well something like this would work on glyocolic acid :) could be a nice way to produce glyoxylic acid. (probably use sodium glycolate since to yield a sodium glyoxylate since its heat sensitive).

Vanadium pentoxide is relatively inexpensive.

Just putting out information. I seem to like nicodems idea.

(edit)
just looked at the msds for vanadium pentoxide, it seems very toxic. LD50s in rats are around 10mg/kg and LD50 for a rabbit via skin absorption was 50mg/kg.

Fortunately the amount needed is very litttle as it is a catalyst but gloves are a definite must. If not being recycled the vanadium pentoxide must be disposed of properly. (Not down the sink!!) It is hazardous for the enviroment).
(/edit)

[Edited on 10-3-2005 by enima]
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CherrieBaby
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[*] posted on 10-3-2005 at 12:35


Here are some azeotropes to avoid:

Water - Nitroethane, bp: 114.07, % 28.5:71.5, bp(az): 87.22
Nitroethane - n-hexane, bp: 68.74, % 10.6:89.4, bp(az): 59.4
Nitroethane - n-butanol, bp: 117.70, % 55:45, bp(az): 107.70
Nitroethane - toluene, bp: 110.75, % 25:75, bp(az): 106.2
Acetic acid - Nitroethane, bp: 114.2, % 30:70, bp(az): 112.4

The 3 sets of numbers are (a) b.p. of the 2nd component, (b) ratio of 1st to 2nd, (c) b.p. of the azeotrope.

They don't seem to be too sure what the b.p. of nitroethane is reporting it as: 114.07, 114.2 or 114.8 depending upon what source one uses.

[Edited on 11-3-2005 by CherrieBaby]
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enima
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[*] posted on 10-3-2005 at 19:10


Guess the water to nitroethane azeotrope isn't too bad. I wonder if youd be able to seperate it by saturating the water with NaCl.
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[*] posted on 10-11-2012 at 08:13


Preparation of pyruvic acid by heating a mixture of tartaric acid and potassium hydrogen sulfate.

Organic Syntheses, Coll. Vol. 1, p.475 (1941); Vol. 4, p.63 (1925).

http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv1p0475

Convenient Oxidation of Oximes to Nitro Compounds with Sodium Perborate in Glacial Acetic Acid

Synlett (1992) 337


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[Edited on 10-11-2012 by Mush]
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Methyl.Magic
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[*] posted on 20-11-2012 at 09:38


DMDO really kick asses ! He's in my top ten reagent. He can even oxydise methylcyclohexane to alcohol with 100% yeild. Totally powerful and amazing !

Acetaldehyde is not that hard to get but i'll personally go with the mentioned pyruvic acid route because its seem easier to form the oxime.

Be careful with nitropropionic acid, it's known to be explosive...

I always hear question about OTC nitroethane synthesis but I have never never seen anyone trying the synthesis... what a pity...

FSO3Me
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[*] posted on 20-11-2012 at 10:48


Reference Information


A Versatile Method for the Conversion of Oximes to Nitroalkanes
D. Subhas Basea & G. Vanajathaa
Synthetic Communications
1998, Volume 28, Issue 24, pages 4531-4535
DOI:10.1080/00397919808004517





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