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Author: Subject: 5-ATZ(5-Aminotetrazole), the nitrotetrazolate ion and friends
Rosco Bodine
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[*] posted on 14-3-2007 at 14:26
more metal complex salts


This patent has a few interesting complex salts ,
and also provides some citations of references
which may be of more general interest .

Attachment: US5962808 Metal Complex Oxidizer Salt Gas Generants.pdf (538kB)
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Rosco Bodine
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[*] posted on 14-3-2007 at 18:14
5,5'-Diazoaminotetrazole


Also called

Bis(tetrazolyl)-5)-triazene ,

1,3-Bis(1H-tetrazolyl-5)-triazene ,

I,III,-Di-(tetrazolyl-5)-triazene ,

1,3-Di-[tetrazolyl-(5)]-triazene

The sodium salt is obtained by nitrosation of aminoguanidine
dinitrate or aminoguanidine sulfate , by dropwise treatment with NaNO2 solution added to a sodium acetate and acetic acid buffered solution of the aminoguanidine salt at 15C .
5-aminotetrazole by the same treatment gives the same product . The sodium salt is reportedly not explosive ,
but leads to other metallic salts by metathesis , which are explosive . The lead salt , and the lead double salt with
lead styphnate are particularly interesting .

See PATR vol. 9 page T-121
Lead-5-5'-Diazoaminotetrazolate Styphnate is reportedly
an " ideal replacement " for lead azide .

[Edited on 19-3-2007 by Rosco Bodine]

Attachment: US2064817 Manufacture of Diazotized Tetrazole Derivatives.pdf (98kB)
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Rosco Bodine
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[*] posted on 14-3-2007 at 18:18


US2090745 describes the single
Lead 5-5'-Diazoaminotetrazole salt

[Edited on 14-3-2007 by Rosco Bodine]

Attachment: US2090745 Lead 5-5'-Diazoaminotetrazole.pdf (93kB)
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Rosco Bodine
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[*] posted on 14-3-2007 at 18:30
The " Stabanate " patents


One of the useful things which can can be done with
nitroaminotetrazole


US3310569
Crystalline Double Salt Pb Styphnate and Pb Nitroaminotetrazole

GB1069440 British patent same subject

Attachment: US3310569 Stabanate.pdf (506kB)
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Rosco Bodine
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[*] posted on 15-3-2007 at 00:05
Azotetrazole , 5,5'Azotetrazole


See PATR , Vol.1 , A-569

The sodium salt is produced in 76% yield from a solution of
5-aminotetrazole in 15% NaOH at 50C by oxidation with KMnO4 solution added dropwise . Unreacted KMnO4 is
decomposed with alcohol , and the solution is refluxed for 1 hour at 100C . On cooling the sodium salt is obtained as
crystals .

Attachment: US5877300 5-5'azotetrazole and derivatives.pdf (153kB)
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Rosco Bodine
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[*] posted on 15-3-2007 at 00:29
Lead Azotetrazole


Here is a British munitions patent for the
lead salt of 5,5'-Azotetrazole

Attachment: GB986631 Lead Azotetrazole.pdf (176kB)
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Rosco Bodine
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[*] posted on 16-3-2007 at 13:42
5-Nitrotetrazole


This is one of the energetic tetrazoles which is a bit trickier
to make because of an unstable intermediate diazo compound involved in its formation .
A special technique has been devised for avoiding explosion of the unstable intermediate which otherwise is problematic , and this special method has been further refined and described in a subsequent patent .

[Edited on 16-3-2007 by Rosco Bodine]

Attachment: US2066954 C-Nitrotetrazole Initiator Compounds.pdf (338kB)
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Rosco Bodine
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[*] posted on 16-3-2007 at 13:47
5-Nitrotetrazole improved method


This patent studies and refines the synthesis of
5-Nitrotetrazole , improving the safety and yields .

Attachment: US4093623 Copper Salt intermediate for 5-Nitrotetrazole.pdf (469kB)
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Rosco Bodine
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[*] posted on 16-3-2007 at 14:44
Copper Ammonium Salt of Diazoaminotetrazole


While on the subject of copper salts of tetrazoles .....

Here's an interesting one which I haven't run across before

It seems possible that similar ammonium salt could be possible for silver , zinc , iron , cobalt , chromium and nickel .

[Edited on 16-3-2007 by Rosco Bodine]

Attachment: US2004719 Copper Ammonium Salt of Diazoaminotetrazole.pdf (190kB)
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[*] posted on 16-3-2007 at 15:18


Ok threads merged.

Rosco, thanks for posting all the patents and articles, I know I made mention of a few in the first post, but having them all in one spot online is really conveinent.




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Rosco Bodine
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[*] posted on 16-3-2007 at 15:33
" Green Primaries "


There is a double salt formed from either sodium or ammonium nitrotetrazole , combined with either copper or iron nitrotetrazole as a stable dihydrate .

These compounds are presently being investigated as
relatively non-toxic replacements for lead azide and lead styphnate containing compositions which have been the
established standard primaries in use for many decades .

Attachment: Green Primaries 1.pdf (662kB)
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Rosco Bodine
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[*] posted on 16-3-2007 at 15:42
Present State of the Art


More of the same from Los Alamos
concerning the so called
" Green Primaries "


http://www.sciencemadness.org/scipics/Green Primaries 2.pdf (2.96 MiB)


[Edited on 25-3-2007 by Rosco Bodine]
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Rosco Bodine
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[*] posted on 16-3-2007 at 16:12
Tetrazole Double Salts


Quote:
Originally posted by The_Davster
Ok threads merged.

Rosco, thanks for posting all the patents and articles, I know I made mention of a few in the first post, but having them all in one spot online is really conveinent.


Thanks for merging these threads .

You are welcome concerning the file collection . I was making a dedicated folder of tetrazole related files and decided to share the folder with summary notes and commentary to save others covering the same ground .

It's long overdue to collect most of the pertinent tetrazole related references in one place . I tried not to hop around too much , but to keep the related files together in some intelligent sequence , or as close as I could keep 'em somewhat topically collated .

I still think tetrazoles deserves a sticky thread status ,
to keep from digging it up when it gets pages behind , and avoid a lot of new lookups or newcomers or the lost
posting new topics that are already right there on top in an existing thread .

They are sort of the " top dawg " energetic materials so
as such ....on top is not out of place as a place for the
topic for them to be :D

Anyway , back on topic ...

As a general rule it has been the case that many of the energetic tetrazoles are not satisfactory alone as initiators ,
for being too sensitive , or not having the desired crystalline form and density ....however the same tetrazole salts also
as a general rule form double salts , either combining with
other tetrazole salts as in the above described " green primaries " , or in forming basic salts , or some combined basic salts where a basic metal tetrazole is coprecipitated
with a basic picrate or a basic styphnate . Some of these combined salts may have desirable properties which is
more than just the simple sum of the precursors properties
observed separately . There are only a few of these
combined salts reported , which I have been able to find anyway , so there could be many different possible mixed salts , or even possibly "tetrazo-clathrates" :D , which have
not been reported , and some of these materials could have excellent properties as initiators . The idea is not new ,
and the attached patent gives some insight into one method of coprecipitation , where the combined solution of the sodium salts of the acidic energetic tetrazoles and/or other acidic energetic materials is run into a solution of the lead salt or other metallic salt , resulting in a coprecipitation of
the mixed salt . There are other strategies for the formation of mixed salts , but this is a good one as a starting point for
such experiments .



[Edited on 16-3-2007 by Rosco Bodine]

Attachment: US1580572 Tetrazole Double Salts.pdf (143kB)
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[*] posted on 16-3-2007 at 18:35


US patent 4093623 in regards to the synth of nitrotetrazoles is the one which I found to work well, albeit a large volume and a volumous sludge of a precipitate of the Cu-nitrotetrazole. Gravity filtration should not even be considered, and a small ammount of final yield comes from a large volume of sludge necessitating a disporportionately large buchner funnel for filtration. This is what severly limits all nitrotetrazole synthesis that I have read.

It appears the green types or primarys are starting to come on the market, in the form of nontoxic primers.
http://www.sellier-bellot.cz/nontox-cartridges.php?product=1...
No idea the composition though...




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Rosco Bodine
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[*] posted on 16-3-2007 at 22:01


I don't know if this has already been tried or not .

Something from the " Green Primaries 1 " development
may be applicable here , so that instead of the acid
copper salt of nitrotetrazole being the intermediate ,
which has filtration problems ....possibly the crystalline
" green primary " double salt , Na2[Cu(NT)4]-2H2O could be produced directly . If workable this would avoid having to digest the acid copper nitrotetrazole with
caustic soda to produce the sodium salt and then subsequently reacting that with copper nitrate to form
the double salt " green primary " .

Possibly using Copper Nitrate , easily made from copper carbonate and HNO3 if necessary , and using HNO3 for the mineral acid would be better than using the copper sulfate and sulfuric acid . These would simply be substituted in the method of US4093623 , in proportions
which would favor the formation of the double salt
" green primary " .

Running the two solutions of equal volume simultaneously and slowly in separate equal streams into the mixing and reaction vessel might give a denser precipitate .

The completed addition mixture is held at reflux for five hours and cooled for crystallization in the synthesis reported for the green primary Na2[Cu(NT)4]-2H2O ,
and that extended heating is possibly for crystal growth ,
as I would expect the actual chemical reaction is not
sluggish , but rapid .

I have not performed this reaction so I have no direct knowledge of this or what may happen . It very well could be that simply holding the acid copper nitrotetrazole
precipitate of the US4093623 patent at a high temperature of say 95C or so for several hours might
cause sufficient crystal growth to produce a readily filterable product . It is understandable how there may be some reluctance to subject these materials to digestions at elevated temperatures :D , for fear of
that proverb involving curiosity and cats being realized ,
as much as any expectation of improvement on a process .

However , von Herz did report conversion of the acid copper salt to the sodium salt and copper oxide , under
the condition of elevated temperature , provided by
" boiling aqueous suspension with soda lye ( NaOH) " .
See US2066954 , page 2 , line 3 .

Of course the acid copper salt had been filtered and rinsed free of excess acid prior to this treatment , but
even so this would indicate that possibly the pH could be adjusted for a
" one pot synthesis " of the copper based
" green primary " .....and also that the temperature
could possibly be raised somewhat in hopes of obtaining a more easily filterable acid copper salt by the method reported in the patent .

Another thought I had is that possibly ammonium nitrate , could be used for decomposition of the excess NaNO2
for either reaction strategy . This could possibly not work however because of the possibility of complexation of
the ammonia with the copper .

Quite a few things to ponder about this one , and only some experiments would tell the tale on these things .

Update: attached is the " patent pending " application from
the same inventors concerning several of the green primaries


[Edited on 19-3-2007 by Rosco Bodine]

Attachment: US2006030715 Complex Nitrotetrazole Primary Explosives.pdf (316kB)
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Rosco Bodine
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[*] posted on 23-3-2007 at 10:27
A possible simplified method for aminoguanidine


While studying these tetrazole patents ,
I found a related matter mentioned in a patent
US5041661 (attached) ,
concerning the production of aminoguanidines ,
where the use of guanidine nitrate is described
as the precursor reacted with 1, 2, or 3 moles
of hydrazine to form mono , di , or triaminoguanidine nitrate .

The reaction follows the same course essentially as when
nitroguanidine is reacted with hydrazine to form nitroaminoguanidine ......but using guanidine nitrate
leads to a non-nitro , plain aminoguanidine product .

It seems likely that aminoguanidine bicarbonate could be made and isloated from the reaction mixture of *any* soluble guanidine salt with hydrazine sulfate having been digested for a time at the appropriate pH , then treated with CO2 or sodium bicarbonate .

If possible , this would eliminate having to convert guanidine nitrate to nitroguanidine and reduce to obtain the aminoguanidine . Reacting the guanidine nitrate or any other soluble guanidine salt with hydrazine should give the aminoguanidine directly :D

The patent only describes the reaction as being applicable
for the nitrate salt of guanidine , but it would seem to me
likely that any guanidine salt should work as well .

Evolution of ammonia would be a sure sign the reaction is proceeding , if it goes as expected .

If workable this would provide a convenient alternative precursor for those who have a guanidine salt available , but do not have cyanamide .

Attachment: US5041661 Aminoguanidine , Diaminoguanidine or Triaminoguanidine via Guandine Nitrate and Hydrazine.pdf (285kB)
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Rosco Bodine
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[*] posted on 23-3-2007 at 11:34
More of interest concerning triaminoguanidine


It is known that aminoguanidine forms from the reaction of calcium cyanamide and hydrazine sulfate .

The inference I get from reading descriptions of these reactions , is that the mono-aminoguandine being formed
will subsequently add further amino groups to form diaminoguanidine and triaminoguanidine , in the same reaction system , depending upon the availability of
additional hydrazine for formation of the higher ,
poly-aminoguanidines .

Dicyandiamide will reportedly depolymerize in such a reaction system , to provide the mono-cyanamide component , reacting with three hydrazines to form triaminoguanidine .
See US3285958 attached . Possibly also the level of amination of the aminoguanidine produced is also dependant
upon the quantity of hydrazine available for reaction by
this method , and it may be possible to secure the mono-aminoguanidine nitrate , ( or other acid salt ) simply by
adjusting the quantity of hydrazine available in the reaction system to be only sufficient for the desired product .

While the monoaminoguanidine salts are of special interest as tetrazole precursors , the Triaminoguanidine salts are
stable , powerful , useful high explosives also , the nitrate and the picrate are initiator sensitive secondary high explosives , and the perchlorate is a fuse sensitive HE primary which is probably useful as either an initiator or
as a single component charge in detonators . A chlorate
salt and other energetic salts have also been mentioned ,
but their properties have not been described in any of the references I have seen .

Attachment: US3285958 Triaminoguanidine Nitrate from Dicyandiamide and Hydrazine.pdf (298kB)
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[*] posted on 23-3-2007 at 18:51


I just love these nitrogen-rich compound reactions!

The patent mentions the condensation of phenylhydrazine and dicyandiamide. Interestingly, dinitrophenylhydrazine is a common reagent for ketone detection, and thus should be possible to obtain relatively easily. A condensation with dicyandiamide should give (dinitrophenyl-NHNH)2C=N-NH-(dinitrophenyl), or possibly a nitrate salt thereof. Thus a potentially very interesting combo-energetic compound, being a nitrate salt, containing N-N bonds, and nitrophenyl moieties! Not many EM's could claim that!




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Rosco Bodine
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[*] posted on 25-3-2007 at 00:10
Diazoguanidine ( guanylazide )


Guanylazide is also called Diazoguanidine or Azidoformamidine .

As an intermediate for 5-aminotetrazole the guanyl azide
is not isolated but is cyclized with ammonia .

Freeform Guanylazide is unstable and is only isolated as its stable salts .

The guanylazide picrate has been mentioned earlier
on the first page of this thread . It has been patented US2125462 ( attached ) for use as a base charge in detonators .

Possibly the styphnate could also be interesting ,
as styphnic acid could bond with *two* of the guanylazide
groups and unless it tended towards formation of a hydrate ,
it should be more powerful than the picrate . It would also seem possible the formation of a basic lead guanylazide styphnate , and also possible though perhaps less likely ,
a sort of double salt or complex salt of normal lead styphnate
and guanylazide styphnate .

The nitroguanylazide is interesting too , but I have not
found any reference describing its explosive properties ,
except that it is explosive . Whether or not the nitroguanylazide forms stable explosive salts similarly as does the guanylazide is unclear .

Linked below are some other threads which contain information relevant to this thread with regards to precursors and intermediates , particularly of interest being methods based on OTC materials . This list will be lengthened here and/or further along in this thread as time
passes .

OTC Cyanamide
https://sciencemadness.org/talk/viewthread.php?tid=825

Guanidine
https://sciencemadness.org/talk/viewthread.php?tid=1469

Cyanuric Acid
https://sciencemadness.org/talk/viewthread.php?tid=8160


[Edited on 25-3-2007 by Rosco Bodine]

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[*] posted on 29-3-2007 at 06:39
Referring to "Green primaries 1"


I am considering preparing some of the primaries listed in the "Green primaries 1" paper available upper in this thread. However, I have two questions before going further:

- the ferrous complex requires [FeII(H2O)6]Cl2 : I have been searching chem databases for a while, and I didn't find this 6-hydrate chloride, but the 4-hydrate form only. And I don't think it's a typo in the article. If the molar ratio is respected, do you think it could make a difference ?

- is it known if such green primaries are unequivocal ?
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Rosco Bodine
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[*] posted on 29-3-2007 at 07:58


I could be wrong but I would expect that any soluble Iron
compound could be substituted in these syntheses ,
and also for the copper and ammonium variants . I see no reason why such substitutions would cause any problem .
I would avoid the acetates and other organic acid salts completely if possible :D Nitrates would be my first choice .

I believe there is something in the articles which mentioned about a hundredfold variation in the
explosiveness , dependant upon the substituents
for the complex . I'd have to go back and read it again
but I'm sure it is there because I wondered what would be the effect of a potassium substituent on the level of hydration , and couldn't find anything . I figured it was something that they were looking at also within the
experiments that are no doubt still a work in progress .

[Edited on 29-3-2007 by Rosco Bodine]
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[*] posted on 12-6-2007 at 21:42


A previous limitation in the prep of nitrotetrazoles from 5-ATZ was the nature of the acid copper nitrotetrazolate salt, Cu(NT)2HNT,(NT=CN5O2-)

This patent here: http://www.freshpat ents.com/Primary-explosives-dt20060209ptan20060030715.php mentions:
"Ammonium nitrotetrazolate was prepared by diazotization of 5-aminotetrazole in the presence of excess nitrite followed by extraction as the tri-laurylamine salt and displacement by ammonia. Upon addition of stoichiometric amount of ammonium hydroxide, sodium nitrotetrazolate forms quantitatively and is analytically pure."

I have seen nothing in the literature on such a synthesis, I wonder if it is some sort of in-house method at LANL or something?




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[*] posted on 12-6-2007 at 22:46


I've tried to find a detailed direct prep. and isolation for the sodium salt before but was met with much frustration as no authors give details, rather refer it off to the attached article, which refers it off to the unobtainable reference:

Gilligan, W. H., and Kamlet, M. J., Technical Report 76-146 (1976), Naval Surface Weapons Centre, White Oak Labs, Silver Spring, Md, U.S.A. [Microfiche AD A036 0861.

Some info can be gleaned from the attachment though.

"1 H-Tetrazol-5-amine monohydrate was converted into sodium 5-nitrotetrazolate dihydrate by diazotization in the presence of excess nitrite according to the method of Gilligan and Kamlet."

"Sodium 5-nitrotetrazolate dihydrate was prepared from tetrazol-5-amine hydrate according to the method of Gilligan and Kamlet. The product was purified by dissolution in the minimum of boiling acetone followed by filtration and precipitation by addition of an equal volume of hexane. The solution was allowed to cool and the product filtered under suction. Compound was obtained as irregular, chunky white crystals; ignition temp. 202", 210°, 214° (lit. 202°)."

So, anyway. The action of sodium nitrite on the intermediate diazonium salt. It seems like no copper ion needed.


[Edited on 13-6-2007 by Axt]

Attachment: Studies of stab initiation. Sensitization of lead azide by energetic sensitizers.pdf (633kB)
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[*] posted on 13-6-2007 at 01:05


I converted the copper salt to the sodium salt by dissolving it in warm water (it is quite soluble at elevated temps) and adding a stoichiometric amount of NaOH soln to pricipitate Cu(OH)2. Then I kept the suspension at 80-90 C until the hydroxide had decomposed to the oxide to facilitate filtering. Gentle evaporation of the filtrate gave the hydrated sodium nitrotetrazolate.
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[*] posted on 13-6-2007 at 05:49


Quote:
Originally posted by Axt
The action of sodium nitrite on the intermediate diazonium salt. It seems like no copper ion needed.



I find that rather odd, the copper ions are added to prevent detonations from diazotetrazole formed from small droplets of the acidic 5-ATZ solution on the walls of the reaction vessel from reacting with the NOx given off by the reaction and forming the diazotetrazole in percents greater than 2 which spontaneously explode in solution. I wonder what they use to prevent this?


US patent 4093623 and an older, unimproved version, 2006954, detail the process of producing the copper nitrotetrazolate, and from it the sodium salt.
from 4093623;
"During initial experimentation with the von Herz procedure by the U.S. Navy, several problems were encountered. First, during the diazotization there was a continuous series of minor detonations, which while not harmful in themselves, were pschologically disturbing and did on occasion break glassware. Moreover, there was the possibility that the potentially dangerous (in the dry state) acid copper 5-nitrotetrazole salt would be spilled over adjacent surfaces as a result of these detonations. Second, upon completion of the diazotization, the acid copper salt was present as a voluminous gel-like precipitate which required long periods (6 hours or longer) to separate by filtration and to wash free of impurities. This would seriously hamper scale-up operations where large quantities would have to be processed."

Also, as I found a few days ago, the gel like nature of the copper salt can be reduced by doing the addition of 5-ATZ, acid, and trace copper over 3h or so, as opposed to 1.5h as detailed in the patent.

Interesting note at being unable to find synthesis refs Axt, I also been finding that there are often voids of information about these types of compounds.

[Edited on 13-6-2007 by The_Davster]




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