Dinitrodimethyloxamide

[Microtek]

According to PATR 2000, this detonates at 7050 m/s at a density of 1.5 g/cc. This is not remarkable in and of itself, but in "the Chemistry of Powders and Explosives" Davis states that:

" 30 parts of dinitrodimethyloxamide and 70 parts of PETN yield a eutectic which melts at 100 C and can be poured as a homogenous liquid. The cast explosive has a velocity of detonation of 8500 m/s which is equal to that of PETN under the best conditions. "

It is prepared by the nitration of dimethyloxamide with mixed acid ( some preparations use oleum ), and dimethyloxamide is "readily" synthesized by reacting (mono)methylamine with an ester of oxalic acid.
Seeing that methylaminehydrochloride can be prepared from hexamine, it might be worth looking into.

[Mr Cool]

Interesting...
Do you think it has to be an ester of oxalic acid? If free oxalic acid could be used it would be a lot easier.

[Pu239 Stuchtiger]

Chemical formula for "dimethyloxamide"? Oxamide is (CONH2)2...

O=C--O--NH2
...|
O=C--O--NH2

What would dimethyloxamide be? (CONHCH3)2? If so, dimethyloxamide would have to be prepared from an ester of oxalic acid.

(COOCH2CH3)2 + 2(CH3NH2) --> (CONHCH3)2 + 2CH3CH2OH

Any data on dimethyloxamide? There isn't even a mention of it in my chemical dictionary.

[Microtek]

PU239: Yes (CONHCH3)2 is correct. My sources also came up short when I tried to find info on this compound which is one of the reasons I posted this topic. I'm sure there must be one of us who could find out. Maybe Philou or Lagen.

[Hex]

dimethyloxamide is CH3-NH-(C=O)-(C=O)-NH-CH3
It can be made by oxidation of dimethyluric acid (Biltz, Heinrich; Schauder, Hans. J. prakt. chem. (1923), 106 108-72). Some nitration and sythesis information is in US 2400287 (1946)and WO 2001064627 (2001)

[Kalium]

dimethyloxamide is H3CNHC0NHCH3 !!!

[Pu239 Stuchtiger]

I have a lot of difficulty believing that dimethyloxamide is CO(NHCH3)2. I cannot see how that chemical could be a derivative of oxalic acid, oxamide, or anything possessing the came carbon skeleton as oxamide. Source?

[Pu239 Stuchtiger]

A quick search at <a href="http://www.google.com" target="_blank">www.google.com</a> for "dimethyloxamide" revealed the following as the first hit:

[i]N,N'-Dimethyloxamide
???. N,N'-Dimethyloxamide. [ 615-35-0 ]. ?????.
????. ????????. C 4 H 8 N 2 O 2 = 116.11. ...
sansi.363.net/products/N,N'-Dimethyloxamide.htm - 5k - Cached - Similar pages[/]

Dimethyloxamide, according to that company, is (CONHCH3)2.

[Microtek]

If you download COPAE from the forum ftp and look on page 394, you will find a short article on the compound. This is the only info I've found on the subject.

[Lagen]

The dimethyloxamide which is used for making explosives is N,N'-dimethyloxamide,CH3NHCOCONHCH3. Synonym: oxalic acid bismethylamide. It may be obtained by the following routes:
- methylamine (usually a conc. aq. soln.) and an ester of oxalic acid (usually ethyl ester)
- methylamine and ethyl ester of methyloxamic acid
- oxidation of caffoline by alkaline KMnO4 soln.
- oxidation of 1,3,4-trimethyluracil with KMnO4
Some properties: Needles or hexagonal leaflets from H2O, M.p. 209-210°C. Sublimes when heated. Very soluble in hot water, soluble in alcohol, in 41 parts of H2O @ 9.4°C. Density: 1.28-1.31. Decomposed by alkalis to methylamine and oxalic acid.

N,N-dimethyloxamide, (CH3)2NCOCONH2. Synonym: oxalic acid dimethylamide. Obtained from ethyl ester of dimethyloxamic acid and a conc. aq. soln. of NH3. Properties: Platelets from benzene. M.p. 104°C. It is not destroyed by distillation in vacuum. Very soluble in H2O, alcohol, soluble in benzene, chloroform, sparingly soluble in ether. Decomposed by anhydrous HNO3 to dimethylamine, CO2, CO and NOx.

[kingspaz]

if its decomposed by CO2 then it wouldn't be that great since any contact with air would degrade the product, and contact with air can hardly be avoided....but still an interesting explosive.
can methylamine be prepared from ammonia + chloromethane?
NH3 + CH3Cl ---> CH3NH2 + HCl ?....also is the formula for methylamine correct or is it CH5N?

[Pu239 Stuchtiger]

Sorry, this reaction:

NH3 + CH3Cl ---> CH3NH2 + HCl

will not occur. I believe the following reaction would occur:

CH3NH2 + HCl --> CH3NH2*HCl

Methylamine is CH3NH2.

Lagen was saying that dimethyloxamide is decomposed to CO2 (that's just one of the products) by concentrated HNO3; he did not say that it was decomposed by CO2. Read more carefully. :)

[Hex]

Hmmm...I think maybe you should read your own message carefully before jumping on anyone else's mistakes - you say don't think CH3Cl + NH3 --> CH3NH2 + HCl would work, but you then say methylamine hydrochloride would form...that would be CH3NH2 + HCl in my book!! And if you really aren't aware how easy it is to recover the free base from the chloride salt of an amine, I think maybe you should do a bit of reading before you start pontificating....

[Pu239 Stuchtiger]

Firstly, I was referring to him reading a post incorrectly... and I wasn't "flaming" him, so don't jump on me for that. Organic bases usually form compounds with acids; urea nitrate, CO(NH2)2*HNO3, for example. The wording of your post was very confusing, by the way, so sorry if I misinterpreted any statements in your post.

[Lagen]

To prevent further confusion: The N,N-dimethyloxamide mentioned in my post is just FYI. It cannot be used for explosives manufacture, hence the note about its decomposition by HNO3. I have included this because I see N,N'- referred to as just "dimethyloxamide", to illustrate that other methyl derivatives exist with completely different properties.

Anyways, back on topic: I have consulted some lit. for the synthesis from oxalic acid esters, namely Ann. 76, 324; Ann. 184, 51. These refs are VERY vague when it comes to a synthesis procedure. All they say is something along the lines of "Add Oxaläther to a strong methylamine solution with cooling, the product will precipitate, wash it with dilute acetic acid and then with alcohol." Cookbook style recipe :mad: <img border="0" title="" alt="[Wink]" src="wink.gif" /> I believe that by Oxaläther they mean oxalic acid ethyl ester.

There are some more I have not consulted yet (haven't found them so far):
WURTZ, Annales de Chimie et de Physique, 30, 464.
HOFMANN, Proceedings of the Royal Society of London, 12, 382.
Jahresbericht über die Fortschritte der Chemie, 1862, 329.

If anyone has a copy please check it out and let us know. Until then we'll probably have to go with the above recipe... The ref Hex gave mentions dimethyloxamide, however, I could find it mentioned as a byproduct or a decomposition product only. The precursors are somewhat harder to obtain.

[cutefix]

Well, I have found out the nitration of dimethyloxamide as pointed out by Hex in the US patent #2400287.It uses the seldom used anhydrous nitration process.It is interesting anyway;but difficult to carry in home laboratory.

“2grams of dimethyloxamide was added to 100cc of solution made from 10.3 grams N2O5 in 100 cc of CCl4 cc in the presence of 3 gramP2O5.It will make the temperature rise 15-30C and is maintained for 20-45 minutes.
Filter the clear solution to remove the P2O5 and phosphoric acid.
The residual N2O5 was recovered by vacuum distillation and CCl4 was distilled out also.
The residue is crude dinitrodimethyloxamide weighing 3.5 grams.”

[Microtek]

I'm bringing up this old thread because I have now successfully completed a total synthesis of N,N'-dinitro-N,N'-dimethyloxamide ( MNO ). The most tricky part is the production of ethyl oxalate, as it decomposes at elevated temperatures. For this reason, a standard esterification is not so convenient and gives quite low yields. Methyl oxalate is more easily prepared, but methanol is banned in my country.

- 3 g ethyl oxalate was prepared from ethanol, anhydrous oxalic acid and sulfuric acid. Methylamine in aqueous solution was made by free-basing methylamine from methylamine*HCl, which was in turn made from hexamine and hydrochloric acid by the well known process.
- A 50% stochiometric excess of methylamine was added to the ethyl oxalate without cooling, and the mixture was swirled to obtain a suspension of ethyl oxalate droplets in the aqueous phase.
- Within 5 minutes, the aminolysis was complete and a multitude of white crystals settled out of the solution.
- After standing for a few hours ( this long wait is probably not neccessary; it seems to be a very fast process ) the crystals were filtered off and dried at a slightly elevated temperature. Yield was 1.18 g or about 50 % based on ethyl oxalate.
- The dry dimethyloxamide was added to 5 mL HNO3, 90% without cooling ( note that this is a huge excess; according to one article, mixed acids with an excess of 20 % HNO3 is enough to nitrate dimethyloxamide, but this would mean less than 1 mL HNO3 to more than a gram of DMO ).
- The DMO dissolved rapidly and with negligible evolution of heat and the mix was placed in the freezer.
- When it was very cold, 5 mL H2SO4, 96 % was added dropwise while stirring, but without further cooling. The mix was then allowed to stir for another 30 min.
- The reaction mixture was poured over 30 grams of crushed ice to precipitate a white powder which after neutralizing, washing and drying weighed 1.73 g which corresponded to a nitration yield of about 80 %.

A 70/30 mix of PETN/MNO does indeed melt below 110 C and can be poured into molds. Thus far densities have not been so good ( 1.3 - 1.4 ). I have not tried detonating such a melt cast pellet.

[Maniak]

I want to make MNO because I like brizant explosives and now I haven´t got any cast explosive (only my substitution for TNT - mixture RDX and PETN suspensed in DNT with nitrocelulose).
Can you write some details about your aminolyse - is there any catalyst or I must only mix it and it will react?
I have a little ethylamine, so I want to try ethyl-version of MNO. It will be powerless, but I hope mixture with PETN will be castable too...
Thanx

[Microtek]

You only need to mix the amine with the ester and swirl to make a suspension. At least this is the case with methylamine, ethylamine might be less reactive.

[nbk2000]

I was reading a patent on making a blasting agent from formaldehyde and AN that generates methylamine nitrate in situ, which sensitizes the remaining AN.

Now, how would one go about seperating it (MAN) from the AN? Considering how easy the reaction is to do, and the availability of the chemicals, it'd seem ideal for use for making the methylamine precursor.

Addition of a few percent urea optimizes MAN production to almost 1/4 of the reaction mixture, with the unconverted AN being recyclable for the next batch, if you can seperate the two.

The process also produces formic acid as a sizeable by-product (if no urea is used), useful for making diphosgene via chlorination of methyl formate.

[simply RED]

A 50% stochiometric excess of methylamine was added to the ethyl oxalate without cooling, and the mixture was swirled to obtain a suspension of ethyl oxalate droplets in the aqueous phase.
- Within 5 minutes, the aminolysis was complete and a multitude of white crystals settled out of the solution.

Without cooling means the reaction is carried out at room tempetarure?

[Zeitgeist]

Well, here's a doc i have on MAN/monomethylamine synth. I know it's rough, but it seems reasonable.

Add 14g hexamethylenetetramine to 100ml 15% HCl in a 150ml beaker. I was expecting something to happen when I did this - some bubbling or SOMETHING, but nothing happened except a slight temperature rise, so I'd say it'd be safe to add all the hexamethylenetetramine at once.

Stir it with the glass rod until all the hex. has dissolved.

Fill the 500mL beaker with water, put it on the tripod over the burner, and put the 150mL beaker into the hot water. Leave it there to evapourate off as much of the water as possible. Some NASTY fumes come off this. I think they're formaldehyde. They don't really smell, they just HURT. Carbon dioxide will also bubble off.

Quickly scrape the crystals out of the beaker, and put them into the other 150mL beaker. Pour on 100ml acetone, and crush up the crystals with the glass rod. Stir them around lots. Filter out the crystals and put them onto the evapourating dish.

Put the evapourating dish over the 500mL beaker of boiling water, until the crystals are dry.

You need to dissolve the methylamine hydrochloride in water, and add a slight excess of sodium hydroxide SLOWLY. This will effectively make a solution of sodium chloride and methylamine. Heat the solution, and gaseous methylamine is evolved.

Using a glass tube to bubble the methylamine gas given off through about 7 or 8 grams of cold nitric acid (because not all of the methylamine will be reacted). Then boil off the water, and voila!

[Microtek]

Simply RED: Yes it was done at room temp. It is rather entertaining to watch the small suspended droplets of the ester quickly transform into flocks of white crystalline precipitate as you swirl the flask.