DDNP & related compounds: The über thread!

2g of Picric Acid Initiated with 0.3g of DDNP & 0.05g of Lead Azide (Unreinforced Configuration)

This test was the same as the last test, where the lead azide was simply pressed on top of the DDNP, except for using 0.3g of DDNP instead of 0.4g and using 0.05g of lead azide instead of 0.1g. The results were surprisingly better despite using less primary explosives, which after a little head scratching was attributed to the ambient temperature being in the high twenties for this test, versus the low teens for the last couple of tests. Higher temperatures can make explosives more sensitive to initiation and perform better as well.

Look at that fragmentation pattern. Glad I was behind a large tree a safe distance away.

The holes on the right, in the witness plate shots, are from this test.




A test was also conducted, using the same quantities, except that silver acetylide double salts was put in place of the lead azide. There was no detonation in this case, only a very yellow witness plate. The silver acetylide-silver nitrate was made about four years ago, but it still seemed to snap quite well when lit, although much weaker than the azides for a similar quantity.






[Edited on 16-5-2014 by Hennig Brand]

Quote: Originally posted by Jimbo Jones

Thanks for the test with the silver acetylide double salts Brand. I’ve suspected that being a weak primary the DS may fail to kick the DDNP and now this is confirmed. Nice tests mate. Keep the good work!

Quote: Originally posted by Rosco Bodine

The temperature stability data and the KClO3 information is already available I think in references posted earlier in the thread. What would be the purpose of mixing with Al is mysterious.

Quote: Originally posted by Dornier 335A

The silver acetylide double salt is one of the primaries that will detonate without confinement even in microscopic amounts. It is rather weak as primary though. I know that someone had problems setting off ETN with it. It was also outperformed in terms of brisance by nano-Armstrong's mixture. Ral, while aluminium powder usually makes the material stronger, it will also lower the brisance - not exactly what's needed for a primary. [Edited on 17-5-2014 by Dornier 335A]

Table taken from the report, "DDNP a Detonating Explosive", which is widely available on this forum and on the web. I have seen other references as well. I know the sand test doesn't tell the whole story, but it is a strong indicator.



[Edited on 17-5-2014 by Hennig Brand]

Quote: Originally posted by Rosco Bodine

Your feelings, suspicions, and information is not entirely correct. There can be an economy improvement for adding an oxidizer because the performance increase of the mixture allows using less weight of the active component and even less total weight for the mixture as compared to the single component. You need to look at the data. [Edited on 17-5-2014 by Rosco Bodine]

Quote: Originally posted by Hennig Brand

DDNP has extremely high energy, but its initiating ability is normally less than lead azide. [Edited on 18-5-2014 by Hennig Brand]

Friction Sensitivity of DDNP

Well I didn't do my own friction testing, but I found a very good report done by the good people at the Institute of Energetic Materials in the Czech Republic. The journal article is titled, "Sensitivity to friction for primary explosives", by Matyas, et al. I have made jpgs of the three key tables and the conclusions.

Some very interesting findings in my opinion. DDNP truly is very insensitive for a primary explosive. The results for lead azide and the peroxides were also very interesting.

Sciencemadness was also in the list of references again, though I think we really should be higher up on the list.



BTW, reference [6] in the conclusions is Meyer 5th edition.


[Edited on 19-5-2014 by Hennig Brand]

[Edited on 22-5-2014 by Bert]

DDNP Recrystallization by Capillary Action Addition of Water to Acetone Solution

The idea of using a wick is not a new one. The idea of transferring a fluid in a controlled manner from one vessel to another using a wick has been mentioned here and at the old E&W forum. I decided to give it a try since unlike evaporative recrystallization, it would purify the DDNP and would not put a lot of acetone vapors into the air. I first tried a piece of loosely rolled up paper towel, to transfer water from one bowl to another. It took about one hour and fifteen minutes to transfer about 50mL of water, in such an even and slow manner that no human could match it with a pipette and if they tried they would be driven to frustration and then madness.



I next set up a homemade stirrer and a beaker with 2g of DDNP dissolved in ~40mL of acetone, a plastic bowl with water and the same wick from earlier connecting the two. A tiny amount of DDNP fell in the water, which is why it is colored. This time it took about 3 hours to transfer 50mL of water, since the wick was held more vertically, placing more gravitational force on the water in the opposite direction from water travel up the wick.



It worked quite well but the sample is still a bit damp. I want to try and get microscope pictures of the unrecrystallized and recrystallized material by tomorrow for comparison purposes.





It is obvious that there was a significant amount of weight loss again. If it really is mostly impurities that are being lost, is it really a big advantage to lose them? Most of the impurities present are probably quite energetic as well. I suppose the purified material would probably have much better storage stability.


[Edited on 20-5-2014 by Hennig Brand]

Quote: Originally posted by Ral123

If we'll be adding small amounts of azide on top of DDNP, I can add small amounts on top of RDX or MHN, it will be much more effective, I guarantee it. The mine field effect doesn't happen with azide and AP.

Quote: Originally posted by Rosco Bodine

140 pounds of pin pressure should be about optimum for 14 MPa or 2000 p.s.i. that should be about the "sweet spot" for loading compression of DDNP at 7.6 mm column diameter.

Yeah that's about right I think. I just calculated 142.4lbs for a 7.6mm pin and it made me question what I did before. Before I had calculated 100lbs of force, but checking back I see that I was calculating for a 1/4" loading dowel, which would need about 99.4lbs of force to give the 14 MPa of pressure (sweet spot pressure). I suppose I was off a bit because it would depend on the diameter, or cross sectional area, of the column of explosives as well since the explosive will tend to hang together even if the loading dowel or pin is a little undersized.


Yield from Capillary Action Recrystallization Experiment

Just took the yield from yesterdays capillary action solvent addition recrystallization experiment. From 2g of crude product, which was made by method B from the article, "DDNP a Detonating Explosive", 1.3g of very pure crystalline product was obtained or about a 65% yield based on the crude DDNP started with. The filtrate is an extremely dark brown with a bit of red to it (I am not great at describing colors).

Below on the left is a 100X microscope picture of the unrecrystallized product, which no matter how hard I tried to focus in on it or prepare the sample I could not make look like anything other than little clumps. BTW, this crude material is what I have been using for the last few explosive tests. The middle picture is a 100X microscope shot of the recrystallized material. It has very well formed large crystals of yellow DDNP. I may have to try 0.2g of this material initiated with 0.05g or less of lead azide or silver azide to initiate 2g of picric acid. The picture on the right is of the filtrate.



BTW, the DDNP produced using method B from, "DDNP a Detonating Explosive", is not really in as nice a form as I indicated earlier in this thread.

http://www.sciencemadness.org/talk/viewthread.php?tid=439&am...

It is more or less free flowing, but has fairly low density and is quite fluffy and dusty. Although I would have to go back and check that I followed their procedure exactly to the letter.


[Edited on 20-5-2014 by Hennig Brand]

Thermal Stability of DDNP

Static Sensitivity of DDNP

Found a little information on DDNP static sensitivity, though in the body of the report the authors state that the sample was old and they didn't verify its purity. The report is titled, "The Electrostatic Spark Sensitivity of Bulk Explosives and Metal-Oxidant Mixtures", and can be found in the DTIC database. I have made jpgs of the introduction and the table which shows DDNP's static sensitivity curves in relation to several others. The copy is an extremely poor one, but it is still readable for the most part.



On the x-axis of the graph is capacity in micro-microfarads (picofarads), and on the y-axis is static energy in ERGS.


[Edited on 21-5-2014 by Hennig Brand]

2.0g of Picric Acid Initiated with 0.20g of DDNP & 0.05g of Lead Azide (Unreinforced Configuration & 6000psi Loading Pressure)

The loading force was measured this time and found to be about 420lbs, and it would be similar for the last couple of tests as well since it was the same lever, the same loading dowel and the same person was using them in more or less the same way. The loading dowel I have been using for all the tests except for the possible exclusion of the first one or two is a 5/16" hardwood dowel that was sanded down so that it can slide freely in and out of the 7.6mm aluminum casings. The loading force of 420lbs corresponds to about 6000psi (~41 MPa) of pressure on the loading dowel. The picric acid, DDNP and lead azide were all pressed using approximately this same pressure. The DDNP used was the recrystallized material from the capillary action recrystallization experiment.

There was a complete detonation, but a clean hole was not blown through. The piece of steel left in the hole is very thin, however, and is cracked through in several places. The steel scab came off the bottom of the witness plate at very high velocity and blew a hole in the ground over 2 inches deep.

The holes on the right, in the witness plate shots, are from this test.




During the test I noticed the end of a casing still packed full of picric acid from the last failed detonation. The piece of cap can also be seen in one of the pictures.


[Edited on 22-5-2014 by Hennig Brand]

I think you are excessive with the loading pressure and are losing performance for that excess. I think you already posted this chart earlier so you probably know this data.
Have you tried a loading pressure at 140 lbs pin force?

Adiabatic Compression Ignition (a.k.a. The Diesel Effect)

The Fire Piston

This is maybe a little off topic, but I think these little devices do a wonderful job of demonstrating compressive heating. I have built several of these using various materials, and the one shown in the picture is the last one. I was at a yard sale a few years ago and I noticed a box of stainless steel hardware with $10 marked on it. Being interested I dug through the box and at the bottom of the box, and accounting for more than half the weight of the contents, were long 1/4" SS bolts with only a small amount of thread on one end and close fitting SS sleeves to go with them. On inspection the sleeves were found to be seamless, so of course I bought the box. IIRC there were about 30 of these bolt sleeve pairs in the box.

I just dug out my fire piston and took a few pictures. There are lots of YouTube videos of people demonstrating fire piston operation. The tinder I am using is a type of tinder fungus called the Chaga mushroom. About eight or ten years ago, after learning about the Chaga mushroom, I would always stop to collect it whenever I saw it in the woods. My parents started to complain after I had three large cardboard boxes full of it in the living room. Whatever happens I will always have lots of tinder fungus.

Adiabatic compression is compression were theoretically no heat is transferred to the surroundings. This is a very close approximation of what happens when there is rapid compression like in a diesel engine, a fire piston or especially in a blasting cap. The effect is so rapid, that a negligible amount of heat escapes. I think a fire piston makes a wonderful demonstration of this concept. Simply using human power to compress a gas (air) to above the ignition point of tinder makes a very interesting demonstration. IIRC temperatures often reach several hundred degrees Celsius in a fire piston, for a brief moment, at the point of maximum compression.





[Edited on 23-5-2014 by Hennig Brand]

Quote: Originally posted by Rosco Bodine

And the cave man said, Smack! Let there be fire! Fire in the hole! It's magic! Now we're cooking. If a little nitroglycerin was soaked into that ball of tinder ......kaboom.

It is amazing indeed. When I first became introduced to some of these primitive technologies I think I felt a little bit of what the cavemen felt when they first discovered some of these things. I have a science background and it is still quite amazing.

Yeah, I have been making jokes about putting a little nitro in one of those things for a while. Of course you could seriously hurt someone that way with even a tiny amount. Gets people's attention when you suggest it though, that's for sure.

2.0g of Picric Acid Initiated with 0.20g of DDNP & 0.05g of Lead Azide (Unreinforced Configuration)

This test was the same as the last except that about half the loading pressure was used for the DDNP primary and the lead azide primary. Approximately 20MPa of pressure was used to press the primaries.

The results of this test were very similar to the last. However, on close examination of the witness plate it was clear that a thicker scab was blown off in the last test. It was estimated that the scab removed in the last test was approximately 50% thicker. This was, however, a crude approximation based on observation and it would have been difficult to measure accurately.

The holes on the right, in the witness plate shots, are from this test.





[Edited on 24-5-2014 by Hennig Brand]

2.0g of Picric Acid Initiated with 0.20g of DDNP & 0.05g of Lead Azide (Unreinforced Configuration)

This test was the same as the last except that the last 0.5g of the 2g picric acid base charge was pressed at approximately 20MPa, or about half the pressure used to press the bottom 1.5g. As in the last test, the DDNP primary and lead azide primary were pressed at the lower 20MPa pressure.

There was noticeable improvement in comparison to the last test. A clean hole was not blown through, but there was a hole torn through and the scab removed from the back of the plate was similar in thickness to the one removed in the second last test where the base charge and primaries were pressed to higher density.

A different cap casing, as suggested by Rosco, could improve performance. The picric acid I am using is over 98% pure, as determined by melting point, but my melting point apparatus is not accurate enough to be able to determine if the sample is closer to 98% pure or 100% pure. The cap diameter could likely be reduced from 7.6mm. The Chinese primary explosives presentation, discussed earlier in this thread, specified 6mm casings for DDNP (but also a reinforced configuration). The casings could, for instance, be reduced to 6.5mm. This would reduce the primary explosive weight needed and would be a large enough diameter for the picric acid base charge to still function properly. There are likely other small factors that could possibly be changed which could reduce the minimum primary explosive weight needed.

The holes on the right, in the witness plate shots, are from this test.




[Edited on 24-5-2014 by Hennig Brand]

Thanks for the good ideas. I have seen the progressive loading pressure idea in a patent or something before, but I never really applied it before except for lately with these DDNP tests. Of course there are different levels of understanding. When I first saw the concept in a patent, my understanding and ability to apply the concept was much less than it is now.

I just had a thought that a possible improvement could be a bushing to reduce the diameter (increase the thickness) of the lead azide top charge, or increased lead azide top charge weight, but after consulting the attached table from the Matyas text it became clear that the 0.05g of lead azide pressed like it was in a 7.6mm casing was actually just about the right amount to give a slab thickness producing maximum or near maximum lead azide detonation velocity.





[Edited on 24-5-2014 by Hennig Brand]

DDNP Electrostatic Sensitivity

Here is another reference for DDNP electrostatic sensitivity. The attached table was taken from the Matyas text.

DDNP is significantly sensitive to electrostatic discharge, but it would seem that it wouldn’t normally pose the same hazard as most other primaries would if they had similar static sensitivity. From Matyas, “Upon ignition, unconfined and unpressed DDNP burns like nitrocellulose even in quantities of several grams. It does not ignite or detonate under water even when initiated by a blasting cap.” The text, “Military Explosives”, also states that a spark falling into the open end of a detonator containing pressed DDNP causes only ignition and flashing of the DDNP (no detonation).





[Edited on 27-5-2014 by Hennig Brand]

2.0g of Picric Acid Initiated with 0.20g of DDNP & 0.05g of Lead Azide (Unreinforced Configuration & 7.6mm X 6mm Bushing)

This test was the same as the last except that after the picric acid base charge was pressed into the 7.6mm id aluminum casing an aluminum bushing was added (7.6mm X 6mm) to hold the DDNP and lead azide primaries. The bushing was made from a piece of 5/16" aluminum round stock. As in the last test the top 0.5g of the 2g picric acid base charge was pressed using half the pressure of the bottom 1.5g (~20MPa versus ~40MPa). The DDNP and lead azide were only hand pressed because a suitable loading dowel, which could be used with the press, for the 6mm id diameter bushing would have had to be made. I really should have taken the time to make one, but the results were quite good in spite of lower primary density. Previous tests would indicate that if the DDNP and lead azide primaries were pressed to higher density that there would be even higher output obtained from the picric acid base charge.

The 2g picric acid base charge detonated with high output; similar to several of the earlier tests where a larger quantity of primary explosive was used. I was really unsure of what the outcome of this test would be, and was happy to get such a good result.

Reducing the primary explosive charge diameter from 7.6mm to 6mm may not sound like a lot. However, if you consider that cross sectional area is proportional to the diameter squared, the cross sectional area at the reduced 6mm diameter is only about 62% of what it is at the larger 7.6mm diameter.

The hole on the right, in the witness plate shots, is from this test.





[Edited on 27-5-2014 by Hennig Brand]

iso-DDNP

There is a less well known isomeric form of DDNP which is reportedly more temperature stable and possible to obtain from an easier synthesis. The acetyl derivative of isopicramic acid which is the most convenient precursor may be obtained by direct nitration of paracetamol, acetaminophen, which is a low temperature nitration under relatively mild conditions.

GB24409 describes a nitration of acetaminophen to the dinitro compound that is the acetyl derivative of isopicramic acid or more probably is isopicramic acid.

The patent describes 15 parts acetaminophen being dissolved in 75 parts sulfuric acid at 0 C and nitration is accomplished by adding gradually with cooling, 44 parts of a half and half mixture of sulfuric acid and 60% nitric acid.
After standing for several hours the nitration mixture is added to 200 parts of ice and the acetyl isopicramic acid precipitates and is filtered out. Heating the acetyl derivative of isopicramic acid with dilute sulfuric acid should hydrolyse and split off the acetyl to produce the isopicramic acid.
See the Meldola and Stephens article page 1204, for the parallel. I am not certain that a deacetylation of the acetylisopicramic acid will occur the same way, and the literature is unclear on this point. A later article opines that one acetyl is already split off from the "diacetyl" derivative of acetaminophen when it is initially dissolved in the sulfuric acid. See page 1937 of the later Meldola article.

Diazotization carried out the same way as for DDNP, but using isopicramic acid provides the isomer of DDNP.

There has been some discussion before about possible nitrations of acetaminophen and what usefulness about that nitration may be, and this would seem to be a relatively easy synthesis.

Relevant references are attached. I'm sure there are probably more pertinent references. It would seem like there should be some published study comparing the properties of the two different isomers to identify their similarities and differences. What may be the difference in the DDT behavior would be particularly interesting for example. Also what is the density difference and does there form a mixed crystal for the two isomers cocrystallized.

The isomeric form of DDNP may be a better initiator, and its derivatives likewise could be better. So this is probably worth experimentation. I may be rediscovering some lost art here, because I am not finding much of anything as references. But it looks to me like this proposed synthetic scheme should work. An uncertainty involved is with the deacetylation of the acetylisopicramic acid, but I am hopeful that it will hydrolyze to isopicramic on heating with dilute sulfuric acid. The literature is not clear on this point.

Attachment: GB24409 o-nitro-o-amido-p-acetamidophenol.pdf (166kB)
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Attachment: Pages from Journal_Chemical_Society_London pg1203.pdf (380kB)
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Attachment: Pages B59-60 from PATR Vol. 2 B-C.pdf (225kB)
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Attachment: Pages from Journal_of_the_Chemical_Society pg1935.pdf (423kB)
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An additional reference has been found, regarding what appears to be the deacetylation of the acetylisopicramic acid, Meldola and Hay article page 1482. But this is still being sorted out. Evidently the deacetylation is tricky and the isopicramic acid (or yet another isomeric analogue?) is unstable. Comparison with isopicramic acid obtained by different method will be needed to determine if this is the same isopicramic acid or yet another isomer.

Attachment: Pages from Journal_Chemical_Society_London pg1482.pdf (427kB)
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An additional reference describes a different approach for synthesis of isopicramic acid.

Attachment: Pages from The_Chemical_world pg327.pdf (247kB)
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The apparent nexus found in the literature are these last two articles by Meldola, evidently illustrating though not explicitly identifying two similar and somewhat analogous syntheses of isopicramic acid. The Journal of Chemical Society article pg1482-1483 describes the isopicramic acid gotten from nitration of acetaminophen, paracetamol to form the acetylisopicramic acid then hydrolyzed using sulfuric acid.

The article from Chemical World describes a slightly different approach involving a benzoyl derivative instead of the acetyl derivative of aminophenol, however the nitration and hydolysis by use of sulfuric acid to leave isopicramic acid as the resulting end product seems to be analogous. It would also seem likely the ammonium salt of isopicramic acid to facilitate isolation may be applicable for the acetyl as well as the benzoyl derivative. The ammonium salt of isopicramic acid is likely stable and would probably be the desired form for isolation of the isopicramic acid. On page 1482 the characterization of the isopicramic acid as having feebly basic properties is possibly a misprint or editing error, as my expectation would be that the compound isopicramic acid is acidic, doh , and would form the salt that is ammonium isopicramate. Perhaps isopicramic acid is amphoteric? The description is confusing unless it is a typo. The isopicramic acid likely is amphoteric similarly as is aminoacetic acid.

I am skeptical about the literature descriptions of structurally different 2,3 and 2,6 dinitro position identifications made in the early research articles that are more cryptic in light of the statement in the Meldola article on the trinitro derivative on page 1937, identifying "the now well known fact that p-acetaminophenol itself always gives rise to isopicramic acid on nitration". Well isopicramic acid is the 2,6-dinitro-4-aminophenol compound,
http://books.google.com/books?id=rB0TAAAAYAAJ&pg=PA270&a...
so this statement doesn't reconcile with a lot of the previously published analyses already published if I am understanding the literature correctly. Earlier Meldola misidentified (I think) the structure as 4,6-dinitro-3-aminophenol as being the ultimate product.
http://books.google.com/books?id=yJIFAQAAIAAJ&pg=PA157&a...
Obviously for "para" aminophenol (or acetaminophenol) the amino group would be opposite the OH of phenol at position 1 which would locate the amino at ring position 4.

This has been a confusing review because it seems Meldola can't make up his mind about structure or is not being fully clear about what is updated information changing what was identified differently and probably incorrectly IMO before.
The literature seems to show the several researchers were puzzled and not in complete coherent agreement. How well the jello got nailed to the tree is not established. More specific experiments would be needed to further sort out and confirm what is actually occurring.

Picramic acid is the 4,6-dinitro-2-aminophenol compound, given the phenol OH at position 1 and the amino NH2 at position 2 on the C6H2 remaining ring structure.
http://www.caslab.com/4_6-Dinitro-2-aminophenol.php5
Isopicramic acid simply has the 4-nitro and 2-amino groups of picramic acid transposed, the reverse order locations.

A few pages back Philou Zrealone was asking about iso-DDNP
http://www.sciencemadness.org/talk/viewthread.php?tid=439&am...

Quote: Originally posted by PHILOU Zrealone

Also what about detonic properties of Iso-diazodinitrophenol (IDDNP) (see picture hereunder vs usual DDNP)? http://www.sciencemadness.org/talk/files.php?pid=330352&...

It seems possible that the isomer could be a superior primary but that the economics of its use are not favorable in comparison to DDNP. It is also possible that the explosive properties of the isomeric DDNP have never been investigated, or that the investigation was done and remains obscure because of translation not done for the publication. I am not certain I recall correctly, but I may have read in PATR or another publication that the Germans experimented some with the para isomer and preferred it to the better known ortho isomer.
Likewise for the other quinone versus phenol structure analogues described by von Herz in attachments to my reply to the question of PHILOU Zrealone about the para isomer of DDNP a few pages earlier. The PATR article I think is in error about the instability of those compounds and may be a misprint (perhaps "unstable" should read instead "usable"?), but I have no followup information. And the diagram posted by PHILOU Zrealone for the para isomer structure is likewise also I think incorrect. The diagram shows a 3,5 dinitro isomer which is not para DDNP. So there is more to be sorted out about these "errors" that I still think I am seeing in the literature and discussion even here. I sent a U2U to PHILOU Zrealone about this thread updating. Here attached is the correct structure for the para DDNP isomer



In fairness to Reverdin and Meldola I think most of their work is good and is correct, and it becomes clearer with the later articles of Meldola. I think because there was simultaneous research and publication there was a too polite kind of academic courtesy operative for each avoiding repeating verbatim the others work and as a consequence some of the material making most sense needed in regards to our topic of interest was not clearly stated by either one in their published articles, which is our disadvantage. Meldola actually wrote a book that was specific about his extensive experiments but I don't think there is an e-book.
There is nothing in the old literature to indicate that the explosive property reported for the para DDNP was something given due attention, and that the para DDNP was not the object and end product desired but was being described only in passing as an intermediate in synthesis of other compounds. The research focus seemed to be a priority of describing broadly the general chemistry for a class of compounds where the para DDNP was a lesser interest as what was probably regarded a dangerous diazo compound to be avoided rather than investigated further so attention was given to moving right along with mapping the reactions for the more mundane and safer compounds. Dye research seems the likely focus more than was their interest in a new explosive. With the spotlight of more awareness later being given to DDNP the para isomer could have simply been relegated to academic obscurity. So it is intriguing what is the real story not only for the para DDNP but also for the other patent compounds of von Herz.

So, Yes, von Herz was probably Austrian
He probably appreciated structural correctness for quinone
is a sine qua non

And I still have to wonder if the N-methyl isopicramic acid would demethylate under diazotization to form the para DDNP as the same resulting product as when isopicramic acid is diazotized. Nothing I have found in the literature provides any clue. Since Metol is ubiquitous as a film developer then that would seem to be a valid precursor and too good to overlook, even though paracetamol as a starting material could be workable too.

Regarding the amphoterism aspect of these diazo compounds that I mentioned earlier, yes I believe there does exist amphoterism or similar property at least in a qualified sense, and the ready solubility even for DDNP in concentrated HCl versus insolubility in dilute HCl shows this amphoterism for DDNP, along with I think the reactivity of DDNP with certain alcohols like isopropanol which therefore can't be used for recrystallization of DDNP for reason of that reactivity.

Attachment: Isopicramic Acid Pages 243-4 from PATR Vol. 1 A.pdf (169kB)
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Of related interest is that it is possible but difficult to introduce an additional nitro group in the case of an isomer of DDNP so that a 2,3,5 trinitro diazo variant is produced, but the compound is chemically reactive and probably unstable in comparison to the dinitro variants. See attached article by Meldola and Hay as referenced near the end of the PATR excerpt. Also attached is the Meldola and Reverdin article where some revision about structures is made if I understand correctly is a shared impression of Federoff conveyed in the PATR excerpt. It is understandable there could be some variations of structure that would be confusing to the reader trying to track these various isomers that would seem possible and sort it out. I know I suffer from "structure confusion" just reading about all these variants, like the fun never stops....but it gets there eventually.

Attachment: Meldola and Hay Pages JCS Vol95 part2 pg1378.pdf (478kB)
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Attachment: Meldola and Reverdin pages JCS 103 part2 pg1484-94.pdf (766kB)
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Yeah it gets complicated, which is another factor in favor of the para DDNP being not given attention. It was one of several variants that turned up in a complex mapping of related compounds and not nearly as straightforward as the more well known DDNP.

The most interesting aspects of this old research being referenced is the para DDNP isomer and the dinitroquinone diazides patented by von Herz. Both likely have value even though not having received much attention. It seems ironic in a way that there would not be more attention to such energetic materials because they are "green" energetics and that has been so much a point of environmentally conscious motivation and "salesmanship" even though IMO it is a disproportionate concern that is an irrelevant concern for probably most outdoor applications or occasional use scenarios as a practical matter of concern as a source of environmental pollution significant enough to justify being mitigated.

The usual DDNP being used as an initiator was evidently patented first by von Herz according to the application date for the German patent DE373426 a couple of days short of a full year before the Dehn patent filing in the US1404687. The Dehn patent issued earlier but the application date is the invention publication, so von Herz gets credited.

And the associated von Herz patent GB207563 for the variants is what is more interesting still particularly with regards to the resorcinol related compound potassium salt, but also interesting for others. The polyvalent phenols producing analogues of DDNP which retain an acidic hydroxyl and form salts that are energetic makes possible nitrated phenol diazo compounds which are as powerful or more powerful initiators than lead azide.

There was earlier a post about the analogous reduction of styphnic acid
http://www.sciencemadness.org/talk/viewthread.php?tid=433&am...
and in the post following
http://www.sciencemadness.org/talk/viewthread.php?tid=433&am...
I attached the patent US4246052 and other patents.
For convenience I will attach again US4246052 here as this ties in nicely with the precedent earlier art von Herz patent GB207563 and supplies additional information. This may provide an alternative route to the same nitrated resorcinol diazo derivative analogue or a variant of what is earlier described by von Herz gotten by a different method in GB207563.

Attachment: DE373426 Original DDNP patent von Herz.pdf (179kB)
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Attachment: US4246052 SnCl2 reduction of Styphnic Acid and DDNP analogue therefrom.pdf (240kB)
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Attachment: GB207563 Diazidodinitrohydroquinone.pdf (371kB)
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Hopefully the nexus is obvious about these assorted references showing additional possible diazo compounds analogous to or variants of DDNP, some of which are also capable of forming salts with metals and result in energetic compounds that are initiators more powerful than either DDNP or lead azide.

There are potentially useful nitrated benzene diazo compounds obtainable from precursors for diazotization analogous to picramic acid, but resulting in different and in some cases better initiators than DDNP. Some of the precursors may be similar in difficulty to prepare as picramic acid, and others may be easier or more difficult. DDNP is simply one member of a general class of energetic materials where DDNP is one material most commonly known, but other similar compounds are possible. DDNP illustrates a general idea as basis for variants that may be substantially better initiators than DDNP itself. Von Herz identified several examples.

The lead salts reported to exist in both neutral and basic form also makes possible the formation of double or multiple salts and clathrates which could be based upon such basic lead salts and would be more powerful than the multiple salts or clathrates derived from basic lead picrate.


[Edited on 12-6-2014 by Rosco Bodine]

spherical ddnp

I have seen where sodium sulfide is specified to neutralize picric acid a couple of times before already. Check out the process block diagram below. I have also attached the article it came from, sorry, so far I have not found the English translation of it. I guess it could be run through a translator though. It seems like they are really intent on keeping only sodium sulfide and no hydroxide in the reaction mixture, which is interesting. F-1 in the block flow diagram is their specially made crystallization modifier.

Remember most of this work is geared towards industrial processes. Methods used for industrial processes are often not nearly as suitable for small scale.




Attachment: Manufacturing Technology for Spherical DDNP (Chinese).pdf (1.7MB)
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With regards to the usefulness of DDNP in caps, I think there are still a few tricks that we don't know about yet which would likely make DDNP more effective and easier to use as an initiator. It would be nice to see exactly how the Chinese make their DDNP detonators. Also, mass produced reinforcing caps are much less expensive (time, energy, etc) per unit than reinforcing caps made one at a time at home. Is DDNP an effective initator of secondary explosives? I think so. Can DDNP function as a direct replacement for lead azide? I would say definitely no.


[Edited on 19-8-2014 by Hennig Brand]

p-cresol synthesis

Since DDNP requires such a long run up distance to make the transition from deflagration to detonation (DDT), I thought increasing the column length of DDNP while keeping the quantity of DDNP to a minimum might be a good option. A stepped internal diameter, reinforced cap to hold the DDNP might work. Not sure of what the exact dimensions should be. Attached is a sketch of a cross section of a reinforced cap, which illustrates the concept. This could provide much greater DDNP charge length without increasing the mass of DDNP used nearly as much as if a non-stepped configuration was used.

One may even consider to make a bubble inside the detonator so that you get a shaped charge inside the detonator.
The void caused by the bubble would displace explosive material further so for an equivalent weight and section you would get a longer detonator.

The cavity will create a Munroe effect dard with locally focussed over-pressure, temperature and VOD.



[Edited on 28-8-2014 by PHILOU Zrealone]

Was kind of frustrated with the benzofuroxan syntesis, so tried something else instead.

This seems interesting, 2,4-dinitro-6-(tetrazeno-I )-phenol from hydrazine and DDNP, couldn't find anything on tetrazeno benzenes or phenols, could it be that 2-azido 4,6 dinitrophenol is formed instead? The patent calls for a huge excess of hydrazine, I tried on gram scale (1 gram of DDNP in 15 ml water), freebasing 3 grams of hydrazine sulfate under 15 ml of ethanol. When the ethanolic hydrazine solution was added, exotherm developed, gas development (fizzing), immediate dark red colour development. After 2 hours at -20, beautifull dark red long needle like crystals form. Yield looks quantitative. The excess hydrazine does't seem a nessesity at all. What do you guys think? How dangerous would this compound be? (Should have asked in advance probably )

Attachment: US2728760.pdf (159kB)
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A pea size amount of the crystals were taken out with a plastic spoon and pressed almost dry between paper towels. This stuff is alot faster then DDNP when dry. Mtach head amount makes a pop, almost like armstrongs mixture (Colour is also almost the same ) When wet it only smoulders, so I'll leave most of it underwater untill needed.

The potassium salt accelerates even faster, 1/8tst of a match head almost makes a crack and is probably on the edge of detonating.

[Edited on 1-5-2015 by nitro-genes]

DDNP analogue: Styphnamic Acid derivative DDNR

It seems counter intuitive that presence of an additional hydroxyl on the ring, such as for DDNR compared with DDNP, would result in a more powerful explosive than would result from added nitrogen such as the hydrazine derivative of DDNP. But such unexpected results have been observed also for other energetic compounds where the change in explosive power is minimal or even entirely opposite from what would be expected for different substituents or modifications. It is mysterious

I think we might have a winner!

Thanks to Rosco for looking up the references on isopicramic acid, which are not easily found. It seems indeed that the acetaminophen is reasonable stable in mixed acid nitrations.

Three solutions in separate beakers were prepared:

1. 70 grams of NaOH was dissolved in 200 ml water and put at -20 deg. C.
2. 12 g (2.2 mol equivalent relative to the acetaminophen) of absolutely dry ammonium nitrate was dissolved in 30g 98% sulfuric acid at room temperature and then put at -20 deg. C

3. Next, to 60 grams of 98% sulfuric acid was added 10 grams of ethanol extracted acetaminophen. This was heated to 70-80 deg. C. for about 15 minutes to dissolve/sulfonate the acetaminophen. The solution turned a golden orange/brown colour. and then cooled to -20 deg. C.

After all solutions had cooled down to around 0 deg C, the acetaminophen/SA solution was put on an ice-bath (no salt) and the AN/SA mixture was slowly added using a pipet while stirring. Temperature was remained between 5 and 10 deg. C during the addition. The solution gradually turned from orange/brown to deep red/orange, to almost back-red, then with the final additions became more of an orange colour again. Judging from the imediate colour change upon addition of the An/SA, the nitration is very fast, even at this temperature. After 20-30 minutes the addition was complete and the solution was allowed to warm up to room temperature and kept there for another 30 minutes while stirring. Then the solution was then poured in a beaker containing 150 ml crushed ice and water.

The stupid thing is that I had removed the NaOH solution from the freezer when the nitration mixture was put at room temperature, it had warmed up considerably and when added to the ice/nitration mix the exotherm was unmanageable. It heated up to at least 50-60 degrees, I tried adding more ice water from the icebath, but the beaker was too small. Then I decided to add the remaining NaOH solution anyway producing much heat, after which the still slightly acidic solution became an almost black-blueish-red colour, probably hydrolysing part of the acetamino goups. It's in the freezer now and there seems to be a not to shabby amount of blood red crystals at the bottom. Maybe the product obtained is a mix of acetamino-amino compounds and needs further hydrolysation, but is seems really promising at least.

It may actually be that if the NaOH neutralization is done at once and at sufficiently high temperatures, the isopicramic acid is produced immediately, probably at the cost of a slight decrease in yield, due to the (small) remaining amount of HNO3.

I'll try to recrysallize the potassium salt of picramic and isopicramic acid, since the first is a red colour while the latter more brownish according to one of the papers Rosco posted.

[Edited on 18-5-2015 by nitro-genes]