To kick off this thread! This is my contribution. I hope others join in with other compounds and research papers.
Has anyone investigated #2 from this paper. Very promising for a low sensitivity primary. Chemicals don’t look too exotic. I don’t know how to
separate 2 from 6 tho. Less sensitivity than RDX with friction and impact.
There you go: P. Kumar, V. D. Ghule, S. Dharavath, One step synthesis of nitrogen-rich green primary explosives from secondary explosives: synthesis,
characterization, and performance study, https://pubs.rsc.org/en/content/articlelanding/2024/ma/d4ma0....MineMan - 19-2-2025 at 17:18
There you go: P. Kumar, V. D. Ghule, S. Dharavath, One step synthesis of nitrogen-rich green primary explosives from secondary explosives: synthesis,
characterization, and performance study, https://pubs.rsc.org/en/content/articlelanding/2024/ma/d4ma0....
Thank you! Not sure why the link stopped working in a matter of a day! Appreciate you finding this Axt - 19-2-2025 at 19:01
You should have just gone with "Bis-Imidazole and derivatives" as its quite a deep rabbit hole in itself. I don't see strong enough evidence to class
these as "primary" explosives though, that would have to be tested.
Here's preparatory extract from Z. Anorg. Allg. Chem., 2012, 638, 1278–1286. Yield is poor, they claim 40% but a quick glance shows its nowhere near
that. 176 mmol of glyoxal giving 16 mmol of bis-imidazole. Bis-imidazole requiring 3 molar equivalents of glyoxal means the yield is actually 27% (or
1.6% based on ammonia used), dropping to about 14% at the tetranitro derivative. Although the prep itself looks nice, I have all that laying around
assuming they actually used half molar equivalent of metabisulphite where bisulphite is given.
Synthesis of 2,2-Bisimidazole (BI)
Sodium bisulfite (36.6 g, 351 mmol) was dissolved in water (180 mL) and ethanol (100 mL) was added. Afterwards, an aqueous glyoxal solution (25.54 g,
176 mmol, 40%) was added. The solution was stirred for 1.5 hours at ambient temperature. The white adduct was filtered and washed with ethanol and
diethyl ether to yield the glyoxal-sodium bisulfite-hydrate adduct (50.6 g, 175 mmol). The adduct was dissolved in aqueous ammonia (275 mL, 25%) and
ammonium carbonate (10 g) was added. The solution was heated to reflux for 4 hours and cooled down to ambient temperature. After filtration and
washing with ethanol and diethyl ether 2.2 g (16 mmol 40%) could be obtained. The synthesis can be up-scaled by using the fivefold amount of each
reagent yielding 12 g.
Synthesis of 4,4,5,5-Tetranitro-2,2-bisimidazole (TNBI)
Sodium nitrate (18 g 0.2 mol) and urea (0.02 g 0.33 mmol) were suspended in concentrated sulfuric acid (30 mL) at 0 °C. Afterwards, bisimidazole
(5.0 g 37.0 mmol) was added in small portions. The suspension was stirred for one hour at ambient temperature and was subsequently heated to 85–90
°C for 16 hours. After that the suspension was put onto ice-water (100 mL). The product precipitated immediately. It was filtered off and washed with
ice water (4 50 mL) to obtain 6.6 g TNBI·2H2O (51%) as a pale yellow powder.
[Edited on 20-2-2025 by Axt]Microtek - 20-2-2025 at 09:32
There are alternate routes to biimidazole that may be better than that one. I'm attaching a patent that prepares biimidazole from glyoxal and an
ammonium salt (eg. the acetate or chloride) along with some aqueous ammonia.
They report a yield of 78.4 g from 500 g glyoxal solution. As is often the case, there are some issues with the numbers - they say that 500 g 20%
glyoxal is 3.45 mol, which it is not. I'm assuming it should in fact be 40% glyoxal as that would be quite close to 3.45 mol and is also a more common
concentration.
Anyway, the yield is about 50% and the reagents a cheaper than those in the other method. So I think I will try that one.
To be fair, "page not found" is a reasonable response to a search for stable primary explosives.dettoo456 - 21-2-2025 at 14:11
If one has glyoxal lying around, another organic primary could be prepared through cyclocondensation w/ formamide to
1,4-diformyl-2,3,5,6-tetrahydroxypiperazine, then vigorous nitration (WFNA + Ac2O) to the tetranitrate ester. There’s not a whole lot of info
regarding this compound but it’s apparently quite powerful. It’s a nitrate ester, so there are likely going to be some hydrolysis issues and it
does melt before decomp, but apparently the DDT is quick and quite close to the M.P.
Glycine anhydride (2,5-diketopiperazine) can be prepared through strong heating of glycine for several hours in anhydrous glycerol @ 150C. Subsequent
formylation w/ NH4HCOOH and reduction (bakers yeast might do the trick ) would
yield the diformylpiperazinediol, which after nitration may produce a somewhat powerful secondary, 1,4-diformylpiperazine-2,5-dinitrate.
Attachment: currie1967.pdf (835kB) This file has been downloaded 62 times
Microtek - 21-2-2025 at 14:56
Well, I made some 1,4-diformyl-2,3,5,6-tetrahydroxypiperazine for an attempted alternate synthesis of HNIW (I didn't succeed) many years ago. IIRC, it
wasn't very difficult to prepare, though I didn't nitrate it.Axt - 21-2-2025 at 15:31
I feel like that is another article throwing the word "primary" around without evidence, I mean 50cm drop of 5kg weight puts it in the insensitive
secondary category, granted they don't explicitly state that that was the minimum distance but also no detonation on heating. Standard nitration
(KNO3/H2SO4) of DFTHP yields TEX in low yield https://www.sciencemadness.org/member_publications/TEX.pdf
Inositol hexanitrate is structurally related and meant to be very heat sensitive for a purely nitrate ester, although from memory it liked to form
resinous nitration products.
Also structurally related is intermediate to LM-101, (1,4-dinitroinositol tetranitrate) I always planned to try but never did. It's the product of
glyoxal-nitromethane condensation followed by nitration. Its quoted as "very sensitive and should never be isolated dry". Also curious to know if it
has an aci-nitro salt forming state.
[Edited on 22-2-2025 by Axt]vertexrocketry - 21-2-2025 at 16:31
[Edited on 22-2-2025 by vertexrocketry]MineMan - 21-2-2025 at 20:16
Hi everyone! Thank you for the contributions. Axt! I am not familiar with the structuring of molecules, I would like to learn however, maybe there is
a better way than slogging through a 400 page organic chemistry textbook; which frankly is not interesting to me.
But, the purpose of this post was to dive into every rabbit hole of promising non metal primaries, especially insensitive ones. I would still clarify
it as a primary if it DDTs in small mig quantities unconfined or lightly confined. I thought the paper mentions its DDT properties…looking again I
see it does not.
Microtek, thank you for a better synth!
Axt - 21-2-2025 at 23:14
Structures as attached. Of these only cyanuric triazide, DDNP and nitrophenyldiazonium perchlorate have proven and practical, tetraazidobenzoquinone I
have a thread on https://www.sciencemadness.org/talk/viewthread.php?tid=9424#... , easy prep but it's much too sensitive and unstable. The pyridine oxide is also
too thermally unstable igniting below 100C. The nitrates probably aren't initiating explosives in a practical sense, but I translated a passage
regarding inositol hexanitrate. Picture them standing around their inositol hexanitrate campfire :/
There is of course the peroxides in the non-metal category but I don't know of any novel ones that could be called practical.
Hexamethylenediperoxidediazine (hydrazine-formaldehyde peroxide) while quite insensitive failed to detonate as a 0.3g charge in a detonator capsule
bursting with what looked to be deflagration. There has been some published articles on geminal dihydroperoxides that are interesting.
I almost want to try bromonitramines (-NBr-NO2) as primary explosives, it's not a good idea but it is an interesting one.
[Edited on 22-2-2025 by Axt]Microtek - 22-2-2025 at 02:19
I have also been a little leery of the criteria they use for terming something a primary. As MineMan alludes, the ability to DDT reliably in very
small amounts coupled with decent flame sensitivity is key. Just being sensitive to mechanical stimuli is really not interesting although there is of
course a lot of correlation between these characteristics.
But then, this is where we come in: Investigating new (and not so new) compounds and their real world performance in relation to the claims of the
papers.
) would
yield the diformylpiperazinediol, which after nitration may produce a somewhat powerful secondary, 1,4-diformylpiperazine-2,5-dinitrate.