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Boffis
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Thanks for all the information guys. I have spent most of the afternoon reading them and it's going to take me a day or so to crystallize my thoughts
but looking at some of the information I can see several problems.
Engagers data highlight the problem I had foreseen; the need for reducing action. In the example Engager posted they used sodium amalgam but in my
reaction mixture there was nothing that could match this in terms of reducing ability.
In my experiments I quickly discovered that you need to carry out the reactions at 0 - 5C or you simply get lots of nitrogen evolved much as Bancroft
and Beldon observed, they do not really sound to have controlled the reaction temperature and so I presume it took place at room temperature. At the
lower temperatures I used the reaction is slow and very little nitrogen is evolved if the acid is added slowly with cooling. The bright yellow
solution and precipatate also suggests that the reaction is more complex than they give it credit!
It looks like the product I have got is probably either cyanamide or more likely, given its tendency to dimerize, dicyandiamide. Either way I have
plenty material to work on and I can easily test the products. All I need is time!
By the way can any of you guys with access to a library or on line access get:
Buchanon; Ind. Eng. Chem 15, p637 1923
This is one of the references on the Bancroft papers re quantitative tests for the various compounds.
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AndersHoveland
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Thioruea dioxide might be a better reducing agent, instead of the sodium amalgam. I suspect it would greatly increase yields, for although it is a
poweful reducing agent, it would be more selective than elemental sodium, and I suspect that transient tetrazoles formed in solution are rapidly
degraded by the Na.
http://www.sciencemadness.org/talk/viewthread.php?tid=11785
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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Rosco Bodine
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What I would speculate about this reaction scheme involving nitrosation of guanidine to produce cyanamide in high yield is that it should be possible
to then proceed further using hydrazine sulfate to form aminoguanidine in situ followed by a second stage nitrosation to form the guanyl azide, either
isolatable as a salt or further cyclized at modified pH to
5-aminotetrazole. Basically the value of nitrosation of guanidine may prove most useful as a means of obtaining cyanamide under mild conditions, the
cyanamide then being useful for all the subsequent uses for which cyanamide is a precursor. In that regard, then the nitrosation of guanidine to
cyanamide is certainly an interesting and useful item to have available in a chemists cyanogen chemistry toolkit.
This approach to a production of aminoguanidine using hydrazine sulfate and cyanamide gotten by a method
not requiring pyrolytic method may prove to be less complicated than the method using cyanamide gotten by pyrolysis
and subsequently reacted with hydrazine sulfate. A conversion of guanidine nitrate to nitroguanidine which is then reduced to aminoguanidine is also
avoided by a strategy which is a hybrid method drawing aspects from both of the known routes to aminoguanidine. As nitrosation of the aminoguanidine
is required in the further conversion of the aminoguanidine
for aminoguanidine gotten from either a hydrazine or a non-hydrazine route, and given that the synthesis of hydrazine is lower complexity than a
pyrolyitic method for cyanamide, or the synthesis and reduction of nitroguanidine, from a process complexity standpoint, it would seem simpler to use
a hybrid method using hydrazine with a two stage nitrosation which eliminates both a pyrolytic method or alternative reduction, either of which is
followed anyway by one nitrosation.
When details are worked out for this speculated alternative route it may well prove to be the simplest and most direct route to guanyl azide, or
5-aminotetrazole, or stopping reaction at earlier stage an easy source for cyanamide or cyanoguanidine. Nitrosation of guanidine could be a very
versatile synthetic method.
@ Boffis, This is potentially a very nice find if this works out as an alternative mild condition method for cyanamide and hybrid hydrazine method for
aminoguanidine derivatives gotten by nitrosation of guanidine. What I am speculating
here does seem more technically plausible ....yes?
[Edited on 18-7-2011 by Rosco Bodine]
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Engager
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Here are some more refs that may be interesting for tetrazole topic. First 3 refs describe some interesting aspects of 5-ATZ complexing behavior,
complex witch is precipitated in qualitative test for 5-ATZ is one of compounds described in this references. Ref 4 is general review of tetrazole
chemistry and may be interesting for digging ref. links about many tetrazole compounds and their chemistry. Ref 5 contains synth procedures for some
interesting 5-substituted tetrazoles by Schtolle (on German).
Attachment: Complexes of Copper(II) and Some 5-Substituted Tetrazoles.pdf (169kB)
This file has been downloaded 2737 times
Attachment: Metal Tetrazole Complexes Bis-(5-aminotetrazolato)-copper(II).pdf (147kB)
This file has been downloaded 1992 times
Attachment: Complexes of Iron(II) and Some 5-Substituted Tetrazoles.pdf (145kB)
This file has been downloaded 1392 times
Attachment: Chem.Rew-41-1-The Chemistry of the Tetrazoles..pdf (634kB)
This file has been downloaded 12701 times
Attachment: Ber-62-Schtolle-1118-1126(ATZ,OTZ,TZ,ClTz,BrTz,ITz).pdf (634kB)
This file has been downloaded 1261 times
I have tons of references about tetrazoles, i can place them in this topic if somebody interested. 
[Edited on 18-7-2011 by Engager]
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Rosco Bodine
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Surely you must be intrigued by the idea of using urea as a precursor for two different intermediates for 5-aminotetrazole via relatively mild
reaction conditions.
Urea is converted to hydrazine sulfate. A second portion of urea is converted to a guanidine salt such as guanidine nitrate using the silica gel
catalyzed reaction with ammonium nitrate. The guanidine nitrate is nitrosated via sodium nitrite to form a cyanamide solution which is reacted with
the hydrazine sulfate to from aminoguanidine. The aminoguanidine is nitrosated to guanyl azide and cyclized
to 5-aminotetrazole. This may be the easiest pathway yet for having low technical demands for equipment and simple precursors. I think Boffis has
experimented with an easy route to cyanamide from urea by way of guanidine, and this can be exploited as described....although all the reaction
details are not yet thought out, still this would seem to be very feasible as a reaction scheme. This scheme should be more specific for
monoaminoguanidine than the probable mixture of monoaminoguanidine and diaminoguanidine and triaminoguanidine as may be gotten from reaction of
hydrazine directly with the guanidine. Which of these two different reaction schemes may prove better is unknown.
[Edited on 18-7-2011 by Rosco Bodine]
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Rosco Bodine
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@Boffis Please tell us, does your crystalline product obtained from the nitrosation of guanidine melt at about 44C ?
If your product is indeed cyanamide then this is a very useful reaction which
you have found and called to our attention.
There is another reaction which I found which may be of interest regarding guanidine. Reportedly guanidine nitrate
in sodium acetate solution can be reacted with sodium hypochlorite to produce chloroazodine also called azochloramide or azobischloroformamidine.
Possibly this may also have some interest as an intermediate.
http://www.chemspider.com/Chemical-Structure.4880329.html
alternate structure
http://www.chemspider.com/Chemical-Structure.9985.html
[Edited on 20-7-2011 by Rosco Bodine]
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Boffis
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@Engager I'd love to see anything you have on tetrazole, triazole and pyrazole! My interest in these compounds goes way beyond simply things that go
bang! My interest is in their ability to form well crystallised metal salts and complexes eg picrolonic acid and violuric acid.
@Rosco I haven't characterised the products of the reaction yet but I did try to recrystallize a little of the first crop of crystals, they dissolved
slowly but completely but the water boiled before they had dissolved and the remaining solid did not melt, hence the melting point is >100C. Also
most of the material crystallized on cooling and cyanamide is very soluble (about 85gm/ 100ml of water at room temp) only a little would have
crystallized. Dicyandiamide melts at >200C and is much less soluble in cold water (4.3gm/100ml) so this is a possibility but the crystal shape is
much more in keeping with aminotetrazole. After much consideration and reading I think that it is possible that Williams is correct and that 5
aminotetrazole may be prepared directly from guanidine and nitrous acid in a single "one pot" synthesis.
I will post as an attachment in the next day or so my full argument. Where I think Williams was wrong is that he saw this as an incremental reaction
of nitrous acid with amine groups on the same molecule of guanidine were as I now believe that it is a bi-molecular condensation to produce a
transient triazene that then de-arranges to aminotetrazole and a smaller fragment such as formamidine or such like.
It is now clear to me that in my original experiments I used far too much sodium nitrite and that this probably destroyed much of the product via
unstable diazo compound formation and accounts for the poor yield. However, if I'm right about the bi-molecular nature of the reaction the maximum
yield will only ever be 50% from the guanidine. It should be possible to test this theory once I am back in my lab!
As I said I post my full thoughts shortly; they're too long with too many insertions to post peace meal!
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Engager
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I've got some time to read your posts more carefully, apparently your 5-aminotetrazole is a big mistake. There is no way in hell guanidine can form it
in such manner. Product your produced is likely to be nitrosoguanidine, mixed with come cyanamide/urea derivatives.
1. Guanidine reacts with nitrous acid to form nitrosoguanidine as first reaction product.
NH2-C(=NH)-NH2 + HNO2 => NH2-C(=NH)-NH-NO + H2O
2. Diazoguanidine is quite unstable and can easily decompose forming cyanamide, water and nitrogen gas:
NH2-C(=NH)-NH-NO => NH2CN + N2 + H2O
3. Cyanamide is highly reactive and is unstable in acidic environment an is quickly hydrolized forming urea:
NH2CN + H2O => NH2-CO-NH2
4. Urea forms salts with acids, many of them are slightly soluble in acids. Nitrate can be example:
5. Nitrosoguanidine is nasty mutagen so you are welcomed to party.
6. If you think, that you got low yield due to the diazotation of 5-ATZ, you are terribly wrong. Even if process you proposed somehow produced 5-ATZ,
first drops of more nitrite (to form more nitrous acid) will form diazotetrazole, witch is extremely nasty and unstable explosive witch detonates IN
SOLUTION even at 0C without any external stimulus, it can expode even in drops of 5-ATZ solution then drop falls to the flask evolving nitrogen
oxides. I personally grantee you that diazotizing tetrazole is kind of experience that you won't soon forget.
[Edited on 24-7-2011 by Engager]
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Rosco Bodine
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If nitrosoguanidine does form via nitrosation of guanidine, then it is worth noting that nitrosoguanidine may be reduced to aminoguanidine just as
nitroguanidine may be reduced to aminoguanidine, and indeed nitrosoguanidine is an intermediate reduction product during the reduction of
nitroguanidine to aminoguanidine. Personally I would place confidence in the Cornell study of Bancroft and Belden identifying cyanamide as the
nitrosation product of guanidine, however it is known that cyanamide is pH and temperature and
time sensitive, so if the conditions are not carefully controlled it is probable that
dimerization of the cyanamide to cyanoguanidine would occur. Something useful can probably be done with this scheme of nitrosation of guanidine to
produce a number of different products depending upon the reaction conditions . This definitely would make some interesting experiments.
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Boffis
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Hi Guys,
I have already considered these reactions and there are numerous possibilities. I have already considered the nitrosoguanidine reaction (see the
attached pdf of my "thinking document") and I believe the trace contaminant of yellow material in the first crop of crystals to be nitrosoguanidine. I
also discuss the possible nitroso compound + amine compound = azo compound. This could lead to a triazene that may de-arrange to aminotetrazole;
several such de-arrangements have already been published and I have quoted examples.
Take a look at the attached document and have a go at some of the reactions. And please, I found the claim in Williams book difficult to believe too
at first, but as I investigate these reactions it is becoming clear that the chemsitry of urea and guanidines is very complex and very sensitive to
conditions. So simply quoting an equation is meaningless without giving the conditions. I am very aware that I have not proved the identity of the
product of my reactions but equally I can assure you that cyanamide and urea are not important componenets of the first crop of crystals, cyanamide is
too soluble and urea too sensitive to nitrite. After boil down, the second crop of crystals could contain almost anything; cyanoguanidine, melamine
etc but a yellow contaminant is still present.
When I am home next I will try preparing nitrosoguanidine by both routes and then try reacting it with guanidine to see if I can isolate the triazene
and then make it de-arrange to aminotetrazole. As a say in my document I don't see these reactions as a route to cyanamide particularly but almost any
N-N bearing product would be a potential precursor to the tetrazole.
Attachment: My thoughts on the guanidine-nitrous acid reaction.pdf (550kB)
This file has been downloaded 1893 times
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Rosco Bodine
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It appears you probably have the makings of a good journal submission going right here in this thread and with your paper. These reactions generally
are critically sensitive to pH and temperature and other conditions, which can result in three or more ultimate products as the main yield, depending
upon what are the conditions. The nitrosation of aminoguanidine is a perfect example where neutral condition produces tetracene as a guanyl
nitrosoaminoguanyltetrazene product, acidic condition produces guanyl azide, and a pH buffered with sodium acetate / acetic acid, leads to a bis
tetrazole structure diazoaminotetrazole. Cyanamide and cyanoguanidine are also subject to the same steering in their reactions by pH and this has
also been observed in the hydrazine and azide routes. Indeed also the guanyl azide is governed greatly by pH in the course of its reactions as is its
precursor aminoguanidine. It wouldn't be any surprise if a buffered reaction system will be of use in some of these reactions intending a specific
path and end product, maybe a sodium acetate - acetic acid buffer or perhaps a boric acid - sodium borate buffer, during the nitrosation to limit the
reaction pH. I am still trying to understand these interesting reaction schemes which evidently are profoundly affected by relatively subtle
differences in reaction conditions. There's plenty unanswered about mechanisms here to try to wrap ones head around and it is definitely interesting
to dredge up something like this from antiquity and take a deeper look. Interesting paper. I hope you continue investigating this.
[Edited on 25-7-2011 by Rosco Bodine]
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Boffis
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I certainly intend to continue this investigation whatever the products are simply because I am so intriged by the scope to vary the outcome with
subtle changes to conditions. I must admit we need much better control of pH and next time I will monitor pH as well as trying various buffers. I also
intend to run two sets of experiments with 1/4 and 1/2 the amount of sodium nitrite I used before to see how this affects the products. I further
intend to develop the qualitative tests referred to by Bancroft but the silver nitrate test for cyanamide isn't very useful because I'm using chorides
and hydrochloric acid.
I will also try repeating Bancroft's experiments and see if I can isolate the cyanamide.
@Engager You're right clearly no diazotization of aminotetrazole since 30mins boiling down didn't provoke an explosion! However, most of the
intermediates and possible products are sensitive to nitrous acid or nitrites so the vast excess of sodium nitrite I used is likely to have reduced
the yield of any product and generated much nitrogen instead.
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Rosco Bodine
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Engager has a pretty good branched tree diagram of known reactions, but there
are some variations and branches which could be added as we discover them.
Another note should be made that nitrosoguanidine reacts readily with hydrazine to form aminoguanidine. I think aminoguanidine bicarbonate and
probably tetracene as well are kind of waypoint intermediates to be kept in mind because of their low solubility, so any opportunity where a low
solubility intermediate can be gotten to drop out of solution from even a dilute reaction mixture can be exploited, if only as an identifier test for
presence of the components that would lead to those two. I am thinking the same thing with regards to the hydrazine, because of its known reactions it
may be helpful in mapping these nitrosation reactions to identify what may be the unknown product.
With regards to Bancroft's experiment it isn't the isolation of the cyanamide that would be most interesting, but to operate on the presumption it is
present and then react it with hydrazine sulfate or hydrazine nitrate to form the aminoguanidine which could be precipitated as bicarbonate
by adding sodium bicarb. Or perhaps not even bother with
isolating the bicarbonate of aminoguanidine but then further proceed on the presumption it has formed and continue the nitrosation to produce guanyl
azide. What I am thinking is
a one pot synthesis from guanidine to 5-aminotetrazole,
as a bit more complicated than the Williams procedure, but following a course of more clearly identified reactions. Order of addition could be very
critical for example it may be necessary that the cyano product be added to the hydrazine component so the hydrazine appears in excess, or it may
require simultaneous addition so that neither cyano component nor hydrazine component is in excess ....nothing can be taken for granted with fickle
reactions that may not go at all with the dump in a lump methods, or that may be the only way they go....such are the unknowns.
I have a different somewhat general related idea, since triaminoguanidine is another product easily gotten as a result of reactions of hydrazine with
guanidine or cyanamide or cyanoguanidine, and while the energetic triaminoguanidine salts are of already known value, it would seem possible that
other interesting products might be gotten by nitrosation of triaminoguanidine. Tetrazoly azide and by further reduction for 5-aminotetrazole, both
products are obtainable via nitrosation of diaminoguanidine, so the same or closely related materials may be gotten similarly from triaminoguanidine.
[Edited on 25-7-2011 by Rosco Bodine]
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Engager
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Quote: Originally posted by Rosco Bodine  | This is being posted here as nitrotetrazolate related hypothetical material even though the same post is being duplicated in another older thread as a
followup there.
http://www.sciencemadness.org/talk/viewthread.php?tid=10969#...
Guanyl Azide may possibly form an interesting salt with 3,5-dinitro-1,2,4-triazole. I am uncertain how it may be done, but speculate it may be
possible to first form the aminoguanidine salt of 3,5-dinitro-1,2,4-triazole as an
intermediate.
Attached are some references. Guanazole would be gotten from Dicyandiamide reaction with hydrazine as per US2648671. Hydrazine Sulfate could be
converted to the Hydrazine Dihydrochloride via Calcium Chloride and filtering.
Guanazole (DAT) is diazotized to 3,5-dinitro-1,2,4-triazole as per the method described on page 13 of the Los Alamos technical report attached.
The DNT is neutralized with aminoguanidine bicarbonate or
a double decomposition of perhaps a soluble sodium DNT salt with a soluble aminoguanidine salt perhaps the nitrate,
may work.
Then the aminoguanidine 3,5-dinitro-1,2,4-triazole is converted to the azidoformamidinium 3,5-dinitro-1,2,4-triazole per the method used for
conversion of aminoguanidine perchlorate to azidoformamidinium perchlorate. See Klapotke paper attached, regarding compound 4 page 3.
No search has been done for the speculated compound
azidoformamidinium 3,5-dinitro-1,2,4-triazole ....
existence and properties at this point unknown.
Perhaps this could be a "green primary" class material
or a candidate for investigation.
[Edited on 15-6-2011 by Rosco Bodine] |
Synthesis of guanazole is not that easy, especially the separation part. I've actually tried process proposed by the patent but with no luck since
it's much more complicated then one can think. First thing that there is no simple way one can observe reaction taking place without some expensive
lab analytical equipment. No gasses are formed, no color changes, no visible pH change, so you can't conclude that reaction is actually taking place.
Second thing is that product must be separated from ammonium chloride, patent suggest remove solvent in vacuum (since guanazole is oxidized by the
air) and then extract several times with hot methanol, this requires some complicated glassware setup for vacuo and use of methanol witch is quite
toxic and is actually banned chemical in many countries so one can not obtain it without difficulty.
Now on conversion of guanazole to dinitrotriazole. Again process is not that simple, process produce mixture of dinitrotriazole and 5-nitrotetrazole
in aproximately 50/50 quantity with elimination of some CO2. So one will also need to separate this bodies. Salts of dinitrotriazole have not been
well studied even as simple ones as sodium or potassium, only salt of DNT witch is found to be insoluble was silver one. This may give some idea how
to separate 5-NTZ from DNT (for example one can try to precipitate 5-NTZ with some copper salt), however taking to account that salts are not well
studied you can not assume will or not DNT be precipitated by copper as well. So significant effort is reqired for separating this bodies. One more
problem is that reaction intermediates tend to precipitate during diazotizing process what also leads to some potentialy hazardous situation during
this synthesis.
Only way known to produce pure DNT is to use guanazine instead of guanazole. But preparation of guanazine is hell, it is very very difficult and
involves some nasty/dangerous chemicals and is actually even harder then separation of 5-NTZ from DNT. Known routes of synthesis are action of
cyanogen chloride on hydrazine, desulfurising thiosemicarbazide with mercuric oxide, and removing solvent in vacuo since guanazine is very readily
oxidized on the air. I've made attempt to prepare it in this manner some long time ago and can say that this reaction is also hell, very toxic, huge
amount of HgO is reqired to produce even grams of product.... This one is practically unrealistic.
Summarizing statements above it is clear how hard it would be to prepare DNT, in my opinion that is much much harder then prepare 5-nitrotetrazole
instead.
Attachment: US3054800.pdf (130kB)
This file has been downloaded 993 times
[Edited on 27-7-2011 by Engager]
Attachment: Synthesis of guanazine.pdf (245kB)
This file has been downloaded 979 times
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AndersHoveland
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Can 3,5-dinitro-1,2,4-triazole (DNT) not simply be prepared by nitration of 1,2,4-triazole?
[Edited on 27-7-2011 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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Engager
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No. Direct introduction of nitro group is not possible, since nitrogen hetero atoms in the ring deactivate it toward electrophilic substitution.
Literature references state that all attempts to nitrate 1,2,4-triazole directly were unsuccessful.
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Rosco Bodine
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The reaction of cyanoguanidine with hydrazine reportedly is exothermic and complete, producing virtually a quantitative yield, so any problem would be
with isolation of the guanazole from the ammonium byproduct salt corresponding
with the acid which was the hydrazine salt. Really it is only the ammonia which needs to be eliminated, possibly by boiling after basification to
midpoint using sodium hydroxide which hopefully could free the ammonia as a volatile and
leave the guanazole hydrochloride intact. The equimolar sodium chloride byproduct would only be a spectator impurity and would not interfere with
subsequent nitrosation.
Guanazole perchlorate might be of interest itself.
With regards to the byproduct 5-nitrotetrazole, I had also seen that reported
in the patent process but had missed it being an issue mentioned in the Los Alamos paper so that remains an unanswered question. I'll read more on
this
and be thinking about it. There is possibly a better way of doing this.
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AndersHoveland
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| Quote: Originally posted by Engager | | Direct introduction of nitro group is not possible, since nitrogen hetero atoms in the ring deactivate it toward electrophilic substitution.
Literature references state that all attempts to nitrate 1,2,4-triazole directly were unsuccessful. |
Are you sure you are not confusing 1,2,4-triazole with 1,2,3-triazole?
In any case, there is reference in the literature to nitration of N-phenyl 1,2,4-triazole by nitronium tetrafluoroborate, and also similar references
stating that 2-phenyl-1,2,3-triazole can be nitrated with mixed acids, and as the phenyl group can become nitrated into a picryl group, it hydrolyzes
with water leaving nitro-1,2,3-triazole and picric acid.
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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Rosco Bodine
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Guanazole is amphoteric so this may facilitate isolation if there is any intention of doing so, there is probably some metallic "guanazolate" which
might have limited water solubility. Really I see no need for isolation of the guanazole intermediate.
Truthfully the byproduct ammonium salt gotten in the formation of the guanazole might be eliminated in some other way than by basifying and boiling
away the volatile ammonia from the guanazole hydrochloride and sodium chloride brine.
The ammonium chloride simply being left there would not prevent the nitrosation
of the guanazole hydrochloride, but it would be decomposed to nitrogen and water by the nitrous acid which would likewise decompose that much nitrous
acid simultaneously, requiring that more nitrous acid be used to make up the loss.
So it should be possible to proceed with the nitrosation of the crude guanazole hydrochloride and ammonium chloride mixture gotten from the conversion
of cyanoguanidine by hydrazine dihydrochloride. With regards to the mixed product
resulting from the nitrosation being an equimolar mixture of 3,5-dinitro-1,2,4-triazole and 5-nitrotetrazole, more precisely the mixed copper salts,
instead
of or in addition to any subsequent efforts at separation of these materials,
making use of the mixed product to form derived mixed salts would be a
definite interest for experiments. Double salt derivatives could have usefulness
or even advantages.
If the mixed copper salts were digested with sodium carbonate to precipitate the copper and leave a mixed solution of the sodium salts, that solution
could be reacted with guanyl azide nitrate to form the mixed guanyl azide salts derivative and byproduct sodium nitrate.
azidoformamidinium 3,5-dinitro-1,2,4-triazole / azidoformamidinium 5-nitrotetrazole should result as a mixed salt
Alternately, instead of using guanyl azide nitrate, if Azobisformamidine Dinitrate were substituted,
a bridged or mixed salt of the nitro-azolic acids may result as Azobisformamidine 3,5-dinitro-1,2,4-triazole / 5-nitrotetrazole
[Edited on 27-7-2011 by Rosco Bodine]
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Rosco Bodine
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@Engager
Actually the idea of not really needing to isolate the guanazole was either me reinventing the wheel, or my being caught thinking like a Russian,
because this is not a new idea at all. See attached abstract  Perhaps you
could help with that article.
Also it has become known that the diazotization of guanazole can follow three different paths leading to different products depending upon conditions
particularly with regards to the excess of sodium nitrite being used and the acid evidently, so the diazotization condition may be pH related which
would be no surprise.
The Los Alamos report attached here again as in the other thread where some preface discussion was or is occurring
concerning the diazotization of guanazole,
http://www.sciencemadness.org/talk/viewthread.php?tid=10969#...
is illuminating concerning the related patent also from Los Alamos for the production of the ammonium salt of DNT, US4236014 attached. The Los
Alamos report of 1978 on page 10 states that the Los Alamos process was based upon a Russian method published 1970 and cites the Russian publication
reference #15. The Los Alamos related patent for the ammonium salt makes reference to the same Russian publication of 1970. It is not mentioned in
the Los Alamos report of 1978 or the patent applied for 1979 any sort of
dual reaction product resulting from the nitrosation of guanazole which produces 5-nitrotetrazole as when the Sandmeyer method of US3054800 (which you
attached above) is followed and evidently leads to a dual product.
A third reaction route leading to yet a third reaction product, and several other by products is described by US3431251
attached.
Let no one ever think that the chemistry of these related compounds is not sensitive to conditions because certainly
the diazotization of guanazole is a good example how different reaction variables define greatly what is the product.
Whew ....I have the most intense sensation of deja vu as I type this post. So I hope I am not repeating myself for having lost track of having posted
this same thing before.
The inference is clear that guanidine could be used as the starting material and via nitrosation converted to cyanoguanidine, further reacted with
hydrazine sulfate to form guanazole and subsequently by nitrosation again
could be obtained DNT.
Attachment: rjapchem0839_abstract.pdf (3kB)
This file has been downloaded 1081 times
Attachment: US3431251 Diazotization of Guanazole Polymer Product.pdf (105kB)
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Attachment: US4236014_Production_of_the_ammonium_salt.pdf (157kB)
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Attachment: Diazotization of Guanazole to Dinitro Triazole 00312939.pdf (1.2MB)
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[Edited on 29-7-2011 by Rosco Bodine]
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Rosco Bodine
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| Quote: Originally posted by Engager | I've got some time to read your posts more carefully, apparently your 5-aminotetrazole is a big mistake. There is no way in hell guanidine can form it
in such manner. Product your produced is likely to be nitrosoguanidine, mixed with come cyanamide/urea derivatives.
1. Guanidine reacts with nitrous acid to form nitrosoguanidine as first reaction product.
NH2-C(=NH)-NH2 + HNO2 => NH2-C(=NH)-NH-NO + H2O
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Above I made note that nitrosoguanidine can be reduced to aminoguanidine and is in fact an intermediate reduction product when nitroguanidine is
reduced to aminoguanidine.
Of interest also is that nitrosoguanidine readily reacts with hydrazine to form aminoguanidine. It is known also that
subsequent further reaction with additional hydrazine can lead to formation of diaminoguanidine and triaminoguanidine
as the second and yet a third hydrazine react with what
was or may be originally guanidine .....not necessarily having nitrosoguanidine as a starting point. Attached is a single relevant page from the
Lieber and Smith article attached in complete form earlier in this thread. Anyway, it is clear that some parallel pathways are possible in these
complex and intriguing reactions. So let us not be too hasty to rule out alternative paths or possible reactions which may be an easier way of
synthesis for a desired product. Indeed there is sometimes more than one way to skin a cat. Different conditions for reactions can easily lead
through different paths to different products. I think it was Tenney Davis who originated that observation about nitrosoguanidine being produced by
nitrosation of guanidine, and yet there is the different report from Cornell by Bancroft and Belden identifying Cyanamide as the product ....so who is
correct?
The answer is that both reports could be accurate if the reaction conditions were different and each reported accurately what was gotten for their
particular work.
So the devil is in the details With hydrazine inserted
into the reaction in the proper place it can be made to work
in either case, more surely. So this is not a loss even if the
original report of Williams is incorrect or turns out to be a misprint not caught by the editors. It would not be the first time if the Williams
described reaction is indeed a misprint.
I have actually thought it may be aminoguanidine which Williams meant to write as the word where the textbook says guanidine. And a simple misprint
may be the cause of this confusion which has certainly been of some benefit for causing lively debate and investigation. We have identified errors in
print before and this may be another one....or maybe not
Attachment: Page from The Chemistry of Aminoguanidine and Related Substances Lieber and Smith.pdf (21kB)
This file has been downloaded 992 times
In a post above I failed to post a reference and it is too late to edit and attach it to that earlier post so here attached
is the nitrosation of diaminoguanidine to produce tetrazolyl azide or the "tetrazylazide" referenced on page 1 of this thread, supporting further
curiosity about what may result
as a product for nitrosation of triaminoguanidine, which is more easily isolated than the diaminoguanidine.
| Quote: Originally posted by Rosco Bodine | | I have a different somewhat general related idea, since triaminoguanidine is another product easily gotten as a result of reactions of hydrazine with
guanidine or cyanamide or cyanoguanidine, and while the energetic triaminoguanidine salts are of already known value, it would seem possible that
other interesting products might be gotten by nitrosation of triaminoguanidine. Tetrazoly azide and by further reduction for 5-aminotetrazole, both
products are obtainable via nitrosation of diaminoguanidine, so the same or closely related materials may be gotten similarly from triaminoguanidine.
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Attachment: The Reaction of Nitrous Acid with Diaminoguanidine in Acetic Acid Media. Isolation and Structure Proof of Reaction Produ (672kB)
This file has been downloaded 1126 times
Of course it should be kept in mind that depending upon conditions the nitrosation of diaminoguanidine or triaminoguanidine would each be likely to
follow three distinct reaction paths to three differing products as well.
Somewhere along this analysis is where every good chemist
is likely to say out loud... Jesus, Joseph, and Mary !
( I am having great fun with this )
[Edited on 29-7-2011 by Rosco Bodine]
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Boffis
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I can't believe Williams comments were and accident or missprint. There is too much detail given elaborated with formula. He cites no reference though
so we can only assume that it was his own observation. I thing he probably carried out a quick experiment under poorly constrained conditions and
obtained a little amidotetrazole and never followed it up.
The paper on diaminoguanidine seems to highlight yet again the sensitivity of the reaction with nitrous acid to reaction conditions. In an earlier
post there is a reference to the production of 1,5 diamonotetrazole via the same reaction but only over a very narrow pH range. What is so curious
about this reaction is that one mole of sodium nitrite doesn't seem to react or the reaction in reversible.
There's clearly a lot of work to do on the reaction of nitrous acid with guanidine group compounds and I am frustratingly remote from my lab!
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Rosco Bodine
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It is not so difficult for me to follow the simpler reactions proceeding with hydrazine, but the alternate "magic" route of Williams seems less likely
and more complex. I still see the convenience for some of these reactions as alternative
laboratory methods which exploit the use of urea as a starting material, catalytically convertible to guanidine at only moderately elevated
temperature using silica gel and an ammonium salt. For hydrazine sulfate also urea is a starting point, and reportedly by a modified method
semicarbazide can be gotten from urea.
Guanidine nitrate can be dehydrated to ntroguanidine via H2SO4 and reacted with hydrazine to form nitroaminoguanidine, which may be nitrosated to
nitroguanyl azide and cyclized to nitroaminotetrazole as per description on page 1 of this thread.
Alternately nitroguanidine reportedly can be reduced quantitatively to nitrosoguanidine via electrolysis over a mercury cathode in a divided cell
using nickel sulfate to complex the nitrosoguanidine as it forms, and subsequently the nitrosoguanidine may be reacted with hydrazine to form
aminoguanidine. It is anticipated this process industrially may be a cost efficient route and not produce the unrecyclable sludges and difficulties
or costs of alternative methods. See US2835631 attached.
Evidently guanidine can be nitrosated to cyanamide or further dimerized to cyanoguanidine, then reacted with hydrazine dihydrochloride to form
guanazole,
which may be nitrosated to 3,5-dinitro-1,2,4-triazole, or via Sandmeyer to a mixed product 3,5-dinitro-1,2,4-triazole / 5-nitrotetrazole.
And of course if there is a way to react the cyanamide of Bancroft and Belden with hydrazine, then all of the well known reactions which can be done
from there are
available, with the need for a pyrolytic process for cyanamide having been eliminated.
There is nothing I can find about the reaction of nitrous acid with triaminoguanidine. Will the triaminoguanidine simply decompose in reaction with
nitrous acid or is there more probably produced a tetrazolyl azide related analogue product gotten as would be expected from observing the reaction of
nitrous acid with diaminoguanidine which produces tetrazolyl azide?
Having read further references I would amend and correct my statements speculating early in this thread about the troublesome instability of guanyl
azide and nitroguanyl azide, as it has been clearly reported that both materials are isolatable and relatively stable.
The "amidoguanidine diazohydroxide" material which Williams identifies as produced by the reaction of aminoguanidine and nitrous acid at 0 C is
probably tetracene.
I still suspect that there is a misprint in the Williams book which involves the guanidine, should be aminoguanidine, the math doesn't work the way
Williams is showing one too many nitrogens from the first reaction from guanidine, but if it was starting from aminoguanidine then the five nitrogens
would be possible and the first equation would balance.
It would also seem possible that Williams is referencing a rather extreme condition of nitrosation of the guanidine nitrate suspended in concentrated
nitric acid as the verbal description below the drawn reactions describes. This is somewhat analogous to a nitrosation method which has been
patented for production of DDNP. I suspect that if there is an extraordinary chemistry occuring as Williams has described it is probably occurring
under the more extreme reaction conditions.
Attachment: US2835631_ELECTROLYTIC production NITROSOGUANIDINE.pdf (108kB)
This file has been downloaded 943 times
[Edited on 1-8-2011 by Rosco Bodine]
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AndersHoveland
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that is probably because the diazotization of aminoguanidine has loses. when three groups are to be converted on the same molecule, the yield is much
lower due probability. For example, if the yields on one group are 70% conversion, then the yields converting all three groups would be only 34%,
simple probability theory. This is one of the reasons that it is typically difficult to add more than one nitro group to the same molecule.
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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Rosco Bodine
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What you are decribing may seem right, but I think you are only guessing and guessing wrong. Your guess does not square with the 77% yield of
tetrazolyl azide gotten from diazotization of diaminoguanidine, which is comparable with yields of the modified compound gotten from nitrosation of
the analogue monoaminoguanidine. This is totally unrelated so far as I understand to the introduction of nitro groups.
What I was suspecting or by intuition thinking may happen with a nitrosation of triaminoguanidine is that a pentazole or pentazole variant may result
as the product, but that may be an unstable intermediate product which could soon lose nitrogen and partially decompose to a more stable tetrazole,
possibly giving the same tetrazolyl azide as is gotten from diaminoguanidine.
[Edited on 1-8-2011 by Rosco Bodine]
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