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Author: Subject: simple HMX-synth without Ac2O
BASF
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[*] posted on 31-10-2005 at 09:46
simple HMX-synth without Ac2O


Its sometimes cool what you can find while looking for something completely different, initially...

US 2678927

tells us about how hmx can be made in a very simple manner via:

hexamine dinitrate --90% H2SO4--> DPT 30% yield

and in Example 9:
DPT can then be nitrated by means of 99% nitric acid to give HMX in unknown yield.

(You may also have a look on the older thread "HMX by way of nitration of DPT"
https://sciencemadness.org/talk/viewthread.php?tid=738)

Following the data on table 1, the crude product of example 9 contains up to 70% HMX the rest is RDX, which can be seperated by recrystallization with acetone, or destroyed with ammonia sol...

[Edited on 31-10-2005 by BASF]

[Edited on 31-10-2005 by BASF]
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[*] posted on 1-11-2005 at 06:51


There is some interesting stuff there.
Unfortunatly the patent is 10 pages long and Rosco mentioned that the board has a one Mb limit on posts so I can't post the patent as a PDF (or even a zip with all the .TIFF's)

One thing of interest is that it mentions "106 %" HNO3. This is called "absolute nitric acid with enough dissolved nitrogen pentoxide to titrate as 106% acid" - I take that as fuming red - REAL red. Thus that may be an issue as my distilltion equp would have to be altered in some manner to achieve that (and I worked like a dog to get the clear stuff) ;-)
I actually wish I could post it even though it's a big patent as it have some interesting things in it -however it seems in some examples wasteful of acid (it WAS written in '44 just published in 1954)
Another issue is that it produces linear polynitramines which I understand to be rather danerous and undesirable in a production platform (that is why RDX synths have a raised temp component in them; so as to eliminate same).
The patent raises a lot of questions for discussion however. But it's a large work and I wonder if someone has Adobe v6, which has better compression than v5 (which is what I have) maybe someone can squeeze it down to post it. Actually I may try to scan it and post it as a text file because I am keeping this one. It has a lot of stuff that co-incideds with other discussions.
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[*] posted on 1-11-2005 at 17:48


This is somewhat getting off topic but
if you are looking for HMX performance
with * perhaps * less extreme conditions for synthesis , maybe take a look at keto-RDX , having a slight power edge over HMX .

Dinitrourea and HDN are precursors and the process is fairly efficient . The attached file relates to dinitrourea , but includes a reference to keto-RDX . There was some discussion at E&W a year ago , and also there has been general mention of keto-RDX here , but the discussion never really went far .

Attachment: dinitrourea.pdf (85kB)
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[*] posted on 3-11-2005 at 10:15


Quicksilver: "106 % nitric" is not red, it is clear. You produce it by dissolving P2O5 in anhydrous ( or nearly so ) HNO3 to dehydrate it : 2 HNO3 --> N2O5 + H2O forming phosphoric acid in the process.
If you are interested in HMX, you may consider looking for a series of patents by someone called Lukasavage. Also you should look for a google cache of a roguesci thread where Hex and myself discussed these patents among other things.
I tested the procedure starting from DADN, which is HMX with two nitro groups replaced by two acetyl groups.
DADN can be made easily and in 100 % yield from hexamine and Ac2O ( I know you hoped to avoid it, but surely if you can get P2O5... ) in a one-pot synthesis. It is also quite an economical method.
The nitration of DADN to HMX optionally proceeds over SOLEX ( HMX with three nitro and one acetyl ) in which case the yield is essentially 100 %.
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[*] posted on 4-11-2005 at 05:53


Thanks for the hint on the lukasavage pat...though i remember having read these ones. There are also some pats which mention the possibility of generating N2O5 by anodic oxidation of HNO3 in a PTFE-ion exchange membrane fitted cell, although i consider the whole thing as beyond my possibilities. (platinated electrodes, nafion-ion-exchanging membranes etc.)

I wanted to keep the whole thing as simple as possible.
As i (and most others) can´t get my hands on Ac2O(a ketene lamp would be necessary) or P2O5(burning red phosphorus, a restricted substance itself, in dry air) easily, the plan was to make some mg as a scientific project, mainly.
-Starting with 10-20g HMT, and ending with about 1000mg HMX, that would be sufficient.
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[*] posted on 4-11-2005 at 06:15


If anyone would be able to get THIS article i would be very happy:

Study on preparation of dinitropentamethylenetetramine with sulfuric acid process. Bai, Jingrui. Beijing Institute of technology, Beijing, Peop. Rep. China. Huozhayao Xuebao (2001), 24(3), 39-40. Publisher: Zhongguo Bingqi Gongye Di-204 Yanjiuso, CODEN: HUXUFP Journal written in Chinese. CAN 135:359840 AN 2001:589001 CAPLUS

Abstract

Dinitropentamethylenetetramine was prepd. from dense H2SO4 and hexamine dinitrate with formalin as stabilizing agent. The optimum reaction conditions were detd. by orthogonal expt. The product yield was > 60%, and the purity > 98%.

Indexing -- Section 50-2 (Propellants and Explosives)

Explosives
(prepn. of dinitromethylenetetramine with sulfuric acid process)

50-00-0, Formalin, uses
Role: MOA (Modifier or additive use); USES (Uses)
(prepn. of dinitromethylenetetramine with sulfuric acid process)

7664-93-9, Sulfuric acid, reactions
18423-21-7, Hexamine dinitrate




Role: RCT (Reactant); RACT (Reactant or reagent)
(prepn. of dinitromethylenetetramine with sulfuric acid process)

949-56-4P, Dinitropentamethylenetetramine
Role: SPN (Synthetic preparation); TEM (Technical or engineered material use); PREP (Preparation); USES (Uses)
(prepn. of dinitromethylenetetramine with sulfuric acid process)

Supplementary Terms

dinitropentamethylenetetramine hexamine dinitrate sulfuric acid process
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[*] posted on 4-11-2005 at 07:05


It seems possible that HMX could be obtained from the nitroso analogue of DPT , ( DNPT ) which is formed similarly as is R-salt , but in higher yield at a higher pH , via a similar method as for R-salt .

R-salt can be converted to RDX by HNO3 and H2O2 , so it would seem that perhaps DNPT could be converted to HMX by the same method . Although this is not an efficient method in terms of economy , it would not present technical difficulty nor have the requirement for acetic anhydride .

Also there seems to be some discrepancy in the literature about the names for octogen , HMX and " homocyclonite " which in my understanding are all the same compound , as well as different reports concerning the explosive power of the material . It depends on what author and text you are reading , but most of the sources I have seen say that HMX is either on a par with RDX in terms of power , or slightly lower and that its advantage for any practical purposes is that it has greater chemical and thermal stability than RDX , not that it is otherwise superior and certainly not more economical .
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[*] posted on 4-11-2005 at 08:44


I'm not sure if the attached article has done the rounds yet, so here it is. It gives the synthesis conditions that favour RDX, HMX and the linear nitramines via DPT (though using acetic anhydride).

Attachment: cyclic and linear nitramines.pdf (726kB)
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[*] posted on 5-11-2005 at 06:05


Quote:
Originally posted by Microtek
Quicksilver: "106 % nitric" is not red, it is clear. You produce it by dissolving P2O5 in anhydrous ( or nearly so ) HNO3 to dehydrate it : 2 HNO3 --> N2O5 + H2O forming phosphoric acid in the process.
If you are interested in HMX, you may consider looking for a series of patents by someone called Lukasavage. Also you should look for a google cache of a roguesci thread where Hex and myself discussed these patents among other things.
I tested the procedure starting from DADN, which is HMX with two nitro groups replaced by two acetyl groups.
DADN can be made easily and in 100 % yield from hexamine and Ac2O ( I know you hoped to avoid it, but surely if you can get P2O5... ) in a one-pot synthesis. It is also quite an economical method.
The nitration of DADN to HMX optionally proceeds over SOLEX ( HMX with three nitro and one acetyl ) in which case the yield is essentially 100 %.


Actually I am still looking for the whole "106" process. What you said makes sence; but it's tough to get further info on the dynamics of the process itself (weight/volume, etc). The patent made it seem as if the 106 HNO3 was made in situ thus I thought it was some type of red disaster that I fought to avoid :-)
Frankly it IS harder to get Ac2O than P2O5; it's the damn drug issue. You have some interesting stuff on rogursci; I'll check it out.


Axt: thanks for hasseling that PDF, it seems like one (I haven't found it on any FTP) that hasn't been around. Bachmann has done a very large amount of research into nitamines it seems, as he keeps turning up !

[Edited on 5-11-2005 by quicksilver]

[Edited on 5-11-2005 by quicksilver]
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[*] posted on 6-11-2005 at 05:47


Rosco: i did a search for syntheses of DNPT, and it yielded a lot of references. BTW, it seems that DNPT is an important chemical blowing agent in the production of microcellular foamed rubber-products. Possibly, DNPT could simple be ordered...

Some synonyms and commercial trademarks of DNPT:

Registry Number: 101-25-7

Formula: C5 H10 N6 O2

CA Index Name: 1,3,5,7-Tetraazabicyclo[3.3.1]nonane, 3,7-dinitroso- (6CI,8CI,9CI)

Other Names: 1,5-Endomethylene-3,7-dinitroso-1,3,5,7-tetraazacyclooctane; 1,5-Methano-3,7-dinitroso-1,3,5,7-tetraazacyclooctane; 1,5-Methylene-3,7-dinitroso-1,3,5,7-tetraazacyclooctane; 3,7-Di-N-nitroso(pentamethylene)tetramine; 3,7-Dinitroso-1,3,5,7-tetraazabicyclo[3.3.1]nonane; 3,7-Dinitroso-1,3,5,7-tetrabicyclo[3.3.1]nonane; Aceto DNPT 100; Aceto DNPT 40; Aceto DNPT 80; Cellmic A; Cellmic A 80; Cellmic AN; Cellular C; Cellular D; Cellular GX; Cellular L 85; ChKhZ 18; Chempor N 90; Chempor PC 55; Chempor PC 65; DNO/F; DNPMT; DNPT; Di-N-Nitrosopentamethylenetetramine; Dinitrosopentamethenetetramine; Dinitrosopentamethylenetetramine; Dipentax; GP 9; Kempore N 90; Micropor; Mikrofor N; N,N'-Dinitrosopentamethylenetetramine; N,N-Dinitrosopentamethylenetetramine; N1,N3-Dinitrosopentamethylenetetramine; NSC 73599; Opex; Opex 93; PU 55; Pentamethylenetetramine, dinitroso-; Porex F; Porofor DNO/F; Unicel 100; Unicel ND; Unicel NDX; Unicell GP 9; Vulcacel B 40; Vulcacel BN; Vulcacel BN 94
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[*] posted on 6-11-2005 at 05:58


But here the references i found so far.
The process seems to be, as rosco already mentioned, generally a high yielding method of cleaving hmt to the bicyclic pentamethylenetetramine.
As i read elsewhere in an old (homo)cyclonite-patent, hmx could be stable against further oxidation, at least with dilute H2O2(was used to fume off contaminants in the product)...

No.1

Dinitrosopentamethylenetetramine. Krzikalla, Hans; Pohlemann, Heinz; Toepel, Tim. (Badische Anilin- & Soda-Fabrik Akt.-Ges.). (1957), DE 1004618 19570321 Patent language unavailable. CAN 53:99986 AN 1959:99986 CAPLUS

Patent Family Information

Patent No. Kind Date Application No. Date
DE 1004618 19570321 DE



Abstract

Aq. NaOH (50%) 458 was added with cooling and stirring to a soln. (prepd. by treatment of hexamethylenetetramine 1500, NaNO2 1500, and H2O 2250 with 7.5% HCl 8700 parts) at -6 to -12, the mixt. stirred 10 min. at -10 to -6, filtered, the filter cake washed with water until the washes showed a pH value of 7, and dried to give dinitrosopentamethylenetetramine, m. 202-3 (decompn.).


No.2

Dinitrosopentamethylenetetramine. Yoshida, Iwao; Kameda, Hiroaki; Kawatori, Yasuo; Ikeda, Tsukasa. (1964), 2 pp. JP 39021533 19641001 Showa. Patent language unavailable. Application: JP 19620320. CAN 62:59028 AN 1965:59028 CAPLUS

Patent Family Information

Patent No. Kind Date Application No. Date
JP 39021533 19641001 JP 19620320



Abstract

Into a mixt. of hexamethylenetetramine 100, NaNO2 120, and H2O 420 was dropped 32% H2SO4 180, then 25% NH4OH 25 dropped in during 3 min., the mixt. let stand 5 min., H2SO4 48 gradually added to adjust to pH 3.8, NH4OH 25 dropped in again during 3 min., and the mixt. let stand 30 min. to give title product 129 parts, m. 202-5 (decompn.), useful as a foaming agent in the manuf. of sponge-rubber.


No.3

Dinitrosopentamethylenetetramine. Nakamura, Masaichi. Jpn. Tokkyo Koho (1968), 3 pp. CODEN: JAXXAD JP 43027878 19681130 Showa. Patent written in Japanese. Application: JP 19650106. CAN 70:96155 AN 1969:96155 CAPLUS

Patent Family Information

Patent No. Kind Date Application No. Date
JP 43027878 B4 19681130 JP 19650106



Abstract

The title compd. (I) is prepd. by reaction of an aq. soln. contg. 2 equiv. alkali nitrite, 2 NH4 salt of an org. or inorg. acid, and 2 NH3 with 5 equiv. CH2O at 5-10. Thus, 202 g. CH2O was added dropwise to an aq. soln. contg. 54 g. NH4Cl, 69 g. NaNO2, 86 g. 25% NH4OH, and 200 g. H2O with stirring at 5-10 for 3 hrs., then 30 g. AcOH added to the mixt. and the mixt. stirred 5 hrs., and kept overnight. After filtration, washing of the ppt. and drying gave 94% I, m. 208-10 (decompn.).

Patent Classifications

U.S.: 16 E 612.


No.4

The preparation of dinitrosopentamethylenetetramine. Antos, K.; Forman, Z.; Kristian, P. Sloven. vysoka skola tech., Bratislava, Czech. Chemicke Zvesti (1956), 10 162-9. CODEN: CHZVAN ISSN: 0366-6352. Journal written in German. CAN 50:81807 AN 1956:81807 CAPLUS

Abstract

In the prepn. of dinitrosopentamethylenetetramine (I) from NaNO2 and hexamethylenetetramine by acids the optimum yields are obtained only in the pH range 3.5-4.5, which is contrary to results of previous investigators (Bachmann and Deno, C.A. 46, 2085f), showing pH 3-4. I is pptd. at pH 4.5-4.6. AcOH is too weak and even at 17.5% concn. the yield is 57%. Among the mineral acids HNO3 gives the best results and at 12.5% concn. yields as much as 73% I. HCl and H2SO4 give lower results and in concns. above 20% cause rapid decompn. of I. The optimum temp. is -5 to 5. Excess NaNO2 increases the yield by 13%.

Enjoy!
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[*] posted on 6-11-2005 at 06:47


The following abstract from above is quite interesting because of the high yield and simplicity of forming the hexamine in situ as an intermediate .

It seems possible that by varying the reaction sequence with a modification of the pH to a lower value for the nitrosation that R-salt might be formed similarly . You could first form a solution of hexamine from strong ammonia and paraformaldehyde and then nitrosate it to R-salt using the solution of hexamine without ever actually isolating the hexamine as a solid , a technique which I always use for HDN .

And R-salt is a whole lot stronger explosive by itself than HDN . Even if the DNPT doesn't work out to being a good precursor for HMX , this variation of a method for R-salt could prove to be very interesting .

DNPT (I)

Abstract

The title compd. (I) is prepd. by reaction of an aq. soln. contg. 2 equiv. alkali nitrite, 2 NH4 salt of an org. or inorg. acid, and 2 NH3 with 5 equiv. CH2O at 5-10. Thus, 202 g. CH2O was added dropwise to an aq. soln. contg. 54 g. NH4Cl, 69 g. NaNO2, 86 g. 25% NH4OH, and 200 g. H2O with stirring at 5-10 for 3 hrs., then 30 g. AcOH added to the mixt. and the mixt. stirred 5 hrs., and kept overnight. After filtration, washing of the ppt. and drying gave 94% I, m. 208-10 (decompn.).

Patent Classifications

U.S.: 16 E 612.


All that would seem needed for the DNPT to be nitrated to HMX , would be for the nitroso groups to be " oxidized " / nitrated , which generally is not difficult and doesn't require extreme conditions , but the center bridge methylene group would also have to be split out to result in HMX , otherwise if it remained , you would have methylene HMX if such a variation is possible , which might also be a good explosive :D

So it is probably worth looking into , what the further nitration of DNPT may produce . DNPT may simply convert to the DPT , or keep going to form HMX via DPT as a transient intermediate . It would be interesting to see what results from reaction of DNPT upon heating with ordinary concentrated 68-70% HNO3 , as that conceivably may be all that would be needed to do the job of conversion of the nitroso groups all the way to HMX , but that is probably too good to be true . Even if the 1.5 nitric should be required ,
it should take way less to finish the job
since as a precursor , the DNPT is not far from being the desired compound ,
( requiring less 1.5 HNO3 than would be needed for a more usual nitrolysis scheme beginning with an amine as the starting material )

Some very interesting possibilities ! :D
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[*] posted on 6-11-2005 at 08:15


One of the interesting possibilities which seems possible to me is a fusible tertiary eutectic mixture of HMX / RDX / R-salt .

A likely starting point for investigation of such a likely mixture would be 3 parts HMX , 7 parts RDX , and 10 parts R-salt .

The optimum proportions could be different , but I believe such a tertiary eutectic is highly probable , and would make an excellent cast composition for shaped charges :D

Expected melting point should be around
115 C or less .

ps: sorry for not editing message above to add comments , it isn't possible through the current proxy connection
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[*] posted on 6-11-2005 at 10:33


Quote:

A likely starting point for investigation of such a likely mixture would be 3 parts HMX , 7 parts RDX , and 10 parts R-salt .


I wonder how you are able to predict the eutectic mix from above...

[Edited on 6-11-2005 by BASF]
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[*] posted on 6-11-2005 at 12:29


Fuzzy logic from unshaven brain cells
and the following :D

PATR C-632

table for R-Salt Explosives

*reference #12 above the table sure would be a good requested reference translation for any who may have access*

J. Simecek , ChemListy (Czech) 51,
1323-26 , (1957) & CA 51 , 17942 (1957)

Describes use of AN + H2SO4 to convert
R-Salt to RDX

Also see the table of melting points for HMX / RDX mixtures on page 6 of GB615419 . 30% HMX and 70% RDX is the lowest melting mixture .

Urbanski refers to homocyclonite as a different compound , having an extra methylene , something which seems strange naming , because usually the prefix " homo " is used for isomers .
Anyway if RDX can occur with an extra methylene , it would seem that the same would be possible for HMX if a
methylene - HMX were to result from the central bridge methylene of DNPT not splitting off during nitrolysis , which could still lead to a useful explosive .

And if R-salt can be converted to RDX via
NH4NO3 + H2SO4 , then likewise it may be possible to do the same for DNPT and
have HMX as the product by a parallel reaction ....so there are two very good reasons for someone to get the Simecek article cited above .

Ammonium Pyrosulfate might have usefulness in this reaction scheme also .
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[*] posted on 6-11-2005 at 12:53


Guess you could try asking the Czechs: http://pxd.czechian.net/forum/index.php (Maniak are you reading? what does ChemListy refer to?)
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[*] posted on 6-11-2005 at 13:31


I don't speak any Czech at all ,

not even enough to say

journalski artikleski requestski :D

Czech is sort of a Northern Polish dialect right ?;)

I can pick my way through some German and Russian but no such luck with Czech :(

Sure do need some help with this one :D
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[*] posted on 6-11-2005 at 14:46


I was wondering what concentration of CH2O (202g) they used...
I calculated that the used amounts are approx. half of the molar proportions(2,5mol CH2O instead of 5mol and so on), thus also 2,52mol(CH2O)*29g/mol=73,2g CH2O.

73,2g pure CH2O/202g(Total weight of mixture)=0,36
Conclusion: the solution was 36%+ formalin...what a surprise:D

After that they mentioned the molar ratios, it does not seem to play a great role, but considering the pH control in the reaction, the amount of water in mixture could be critical...

Quote:

The title compd. (I) is prepd. by reaction of an aq. soln. contg. 2 equiv. alkali nitrite, 2 NH4 salt of an org. or inorg. acid, and 2 NH3 with 5 equiv. CH2O at 5-10. Thus, 202 g. CH2O was added dropwise to an aq. soln. contg. 54 g. NH4Cl, 69 g. NaNO2, 86 g. 25% NH4OH, and 200 g. H2O with stirring at 5-10 for 3 hrs., then 30 g. AcOH added to the mixt. and the mixt. stirred 5 hrs., and kept overnight. After filtration, washing of the ppt. and drying gave 94% I, m. 208-10 (decompn.).


[Edited on 6-11-2005 by BASF]

[Edited on 6-11-2005 by BASF]
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[*] posted on 6-11-2005 at 15:10


Quote:
Originally posted by BASF
In the prepn. of dinitrosopentamethylenetetramine (I) from NaNO2 and hexamethylenetetramine by acids the optimum yields are obtained only in the pH range 3.5-4.5, which is contrary to results of previous investigators (Bachmann and Deno, C.A. 46, 2085f), showing pH 3-4.


The Bachmann/Deno article is attached into the R-salt thread. http://www.sciencemadness.org/talk/viewthread.php?tid=3453 second from bottom.

The article contains a somewhat longwinded route to HMX.
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[*] posted on 10-11-2005 at 12:31


Successful synth of DNPT!

The first try, which was a disappointing failure:

I choosed No.3 of the refs. in one of my above posts and adapted the quantities to my 20% CH2O.

I used a 100ml erlenmeyer flask fitted with a 4 cm magnetic stirrer.
I prepared an icebath with crushed ice and some AN in which the flask with 7,8g NH4Cl, 10,0g NaNO2, 13,2ml NH4OH 25% and 5,2ml H2O(reduced quantity because of the only 20% CH2O). I waited til the temp inside the flask was adjusted to -10°C.
During the addition of 53ml(quantity adjusted for the lower formalin conc.) CH2O 20% (dropped in within 1/2 hour), there was much fizzing. Despite the low working temperature, the fizzing did not stop after the addition was complete(the CH2O was not precooled).
At this stage of reaction i observed a thin layer of flotating slight yellow/white chrystals, which redissolved to my disappointment after the addition of the 4,2ml glacial acetic acid.
At this point the pH was 3,0-4,5 and the temperature was still -5°C.
Lateron i tried to rub with a glass rod, cool the flask in the fridge, but it did not cause other than freezing out the AcOH.

I can only guess about the reasons for the failure, but it seems that the small quantity of water in the system at the beginning and the CH2O, which was not precooled, could have been main causes, because the procedure i followed lateron(from the bachmann and Deno-article provided by Axt), uses pre-cooled reagent in the addition(NaNO2-sol), and first of all, a huge volume of water (which may help a lot in keeping the HNO2 stable)as compared to the japanese article.


Enough of the failure.
In the 2nd try i used one of the proportions in table III of the Bachmann/Deno-article:

7g HMT, 19,4ml glacial acetic acid(for the HMT/AcOH/NaNO2 1/6/3 mole ratio) in 450ml water in a 500ml erlenmeyer flask, which was stirred with a 4cm magnetic stirrer and precooled together with the 10,4g NaNO2 in 50ml H2O in a AN/ice-bath to -10°C.
The NaNO2-sol was sprinkled in over the course of 5mins, although an addition all at once might also have been possible.
The pH after the NaNO2-addition was 4,0-4,5.
After a few mins, the first flotating yellowish crystals showed at the top.
The flask was stirred for a total of 3h and then the crystals filtered with a folded paper filter and washed with about 20ml H2O. After pressing dry the crystals two times on toilet paper, a semi-dry yellowish powder, 5,36g was obtained.
(The reference states 5,0g yield with the quantities from above, so not that bad)

The melting point (with decomposition) was around 200°C+/-20°C measured by taking up some crystals on the "nose" of the thermometer and holding on a heating plate adjusted to 250°C. The temp. rise was about 1-3°C per second. The ref states a mp. of 206-209°C for DNPT and 106-107°C for the trinitroso-rdx so, easily to tell apart.

[Edited on 11-11-2005 by BASF]
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[*] posted on 14-11-2005 at 12:40


I found another different method starting from urea for the production of DPT:

It´s in "Chemistry of Urea Nitro Derivatives: III. Reactions of N,N´-Dinitrourea with Bases" from Il´Yasov et al.

Dinitropentamethylenetetramine.
Urea, 5g(0,083mol), was added under stirring at -5 to 0°C to a mixture of 10ml of technical-grade oleum(20% SO3) and 10ml of 98% of nitric acid. The mixture was stirred for 30mins at 0-5°C and poured into 30g of an ice-water mixture, and 30ml of a 37% formaldehyde-solution was added at a temp. not exceeding 20°C. The mixture was heated to 40°C, stirred for 20°C, and the ppt was filtered off, washed with water, and dried at room temp. until constant weight. Yield 11g (60%), mp 186-190°C; published data: mp 202-205°C

I´m asking myself: can we substitute the oleum for conc. H2SO4? - maybe by just increasing the quantity(which would also result in a lower viscosity)?


[Edited on 15-11-2005 by BASF]

[Edited on 15-11-2005 by BASF]
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[*] posted on 15-11-2005 at 08:28


It seems like that procedure is missing some nitric acid to be mixed with the oleum. I'd guess around 20 grams.
It does seem a nice straight forward method though; no pH control within narrow intervals, etc.
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[*] posted on 15-11-2005 at 13:33


Oops. I missed part of that sentence while tiping... :P

Now it is okay again. :P
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[*] posted on 15-11-2005 at 13:47


Now i am looking for a suitable method to oxidize my DNPT to DPT. It seems that only absolute nitric acid and the like could do the job:

Nitrolysis of hexamethylenetetramine. III. Preparation of pure cyclonite. Brockman, F. J.; Downing, D. C.; Wright, George F. Can. J. Research (1949), 27B 469-74. Journal language unavailable. CAN 43:50597 AN 1949:50597 CAPLUS

Abstract

Cyclonite (RDX), m. 203-3.5, prepd. from hexamethylenetetramine (I) with HNO3 contg. HOAc, always contains 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclo.ovrddot.octane (HMX), m. 269, as an impurity which is difficult to remove because it is more stable and less sol. than RDX, but it is not present in RDX prepd. by the oxidation of 1,3,5-trinitroso-1,3,5-triazacyclohexane (II), m. 105-7; II is prepd. from I in aq. soln. Although not very stable II is readily purified from the impurity 1,5-endomethylene-3,7-dinitroso-1,3,5,7-tetrazacyclo.ovrddot.octane, formed at the same time.

II reacts violently with strong HNO3 at room temp., usually with inflammation, but does not char at -40 if added to the acid in small portions. The oxidation of II by a mixt. of 82 equivs. of 99% HNO3, 3 equivs. H2O2, and 3.7 equivs. water at -40 yields 45% 1-nitroso-3,5-dinitro-1,3,5-triazacyclohexane (III), m. 176.6, as an intermediate. When III is returned to the same oxidizing mixt., it is converted to very pure RDX, m. 205, in 75% yield. III is contaminated with RDX but is sufficiently sol. in boiling water to allow sepn. from this impurity. No mononitrodinitroso analog is present, indicating that when 2 nitro groups have been established in the cyclomethylenetriamine ring, the 3rd is introduced with somewhat more difficulty.
Oxidizing agents failing to effect the above conversion are: HNO3-NH4NO3, HNO3-H3PO4, HNO3-Ac2O, camphor nitrate, C(NO2)4, Caro's acid, aq. KClO3, neutral hypochlorite, Mn acetate, FeCl3, and HNO3 in MeNO2.
The second thing that bothers me is how to get as low as -40°C. That would be really the absolute edge for inorganic salt/ice-mixtures and i still doubt it. Dry ice?-No source for me, it´s a shame.

BTW, if i get the DPT, how would i be able to identify it? - Nitro- and nitroso compounds seem to have about the same melting points. - Is there any useful reaction to identify it?-Maybe the nitroso-compound decolourizes KMnO4 sol?

If not, the only chance would be to synthesize DPT via well-established methods and make a mixed melting point....:(

[Edited on 15-11-2005 by BASF

[Edited on 16-11-2005 by BASF]
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[*] posted on 17-11-2005 at 08:30


I see there's some demand for Czechs :)
Rosco, no jokes with them! ;)
Actually I can't obtain ChemListy from 1957, but I'll try to ask in National Technical Library.
I'm also interested in HMX synth., but I'd like to use an old process with large quantity of Ac2O and then try to recover it.. The process over DAPT and SOLEX also worth trying, but there are problems with P2O5 handling :(

[Edited on 17-11-2005 by Maniak]
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