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Precipitates
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[*] posted on 24-5-2024 at 20:43


Quote: Originally posted by Yorty2040  
Does anyone have any information on melamine diperchlorate? Solubility, handling, decomposition temp, sensitivity, shelf life, etc?


I could only really find this article on Melamine Diperchlorate Hydrate.

I assume reasonable solubility, not ridiculously sensitive and relatively stable.

[Edited on 25-5-2024 by Precipitates]
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dettoo456
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[*] posted on 28-5-2024 at 08:08


Has anyone carried out a destructive nitration procedure on a ketone before? I couldn’t find much information on them; it seems Russian chemists were messing around with the principles and kinetics in the mid 90s, but those journal entries are very hard to find, let alone translate.

As far as I can tell, it’s basically the same conditions as for the preparation of Nitroform from Acetone (or from the dehydration of IPA and subsequent nitration). Carbonyls, mainly ketones but apparently carboxylic acids as well, undergo decarboxylative nitration to yield the trinitromethyl or dinitromethyl derivative at the alpha position relative to the carbonyl.

This polynitromethyl product though, can be generated by the action of WFNA/H2SO4 with the ketone at 0C, and Hexanitroethane can even be prepared like this in up to a 75% yield from the terminal-trinitro ketone (authors reported using trinitropentanone, though I believe this was a mistake, and trinitrobutanone might have been used instead).

https://www.researchgate.net/publication/250556009_ChemInfor...

This abstract does not provide much insight as to the conditions (molar equivalent, addition rate, extraction), and I couldn’t find the article in the Russian Org Chem journal.

In short, is it plausible that this reaction could be applied to something like MEK, to yield 1,1,1-trinitroethane?
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Yorty2040
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[*] posted on 14-6-2024 at 17:44


So methazonic acid (2-nitroacetaldoxime) can be produced by the base-catalyzed self-condensation of nitromethane, followed by acid workup.

Is there any info on using sodium perborate + glacial AcOH to convert it to 1,2-dinitroethane? The procedure should work, but the devil (and yield) is in the details of the procedure and subsequent workup.
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dettoo456
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[*] posted on 14-6-2024 at 20:14


I’m assuming you’re referencing this paper (linked below) for the oxidation with perborate. As you mentioned though, the preparation will suffer in yields with the scope being so wide (small chain aldoxime already with a nitro substitutient compared to mainly aryl ketoximes reported being used).

A more sketchy method to yield 1,1,2-TRInitroethane could be the ponzio reaction; NO2 or N2O4 in ether or a suitable polar nonprotic at low temperature).

Or, some other, cleaner oxidizer like oxone or H2O2. Though, in any case, including the Perborate/GAA method, oxidation of the aldehyde to carboxylic acid and oxime to carbonyl is probably the reason for such low reported yields.

[Edited on 15-6-2024 by dettoo456]

Attachment: Oxime Oxidation to NO2.pdf (159kB)
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Yorty2040
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[*] posted on 17-6-2024 at 16:22


What's the technical, physicochemical explanation for why complexing the oxoacid salt of a nitrogenous base with a transition metal typically increases sensitivity compared to the uncomplexated salt?

[Edited on 18-6-2024 by Yorty2040]
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dettoo456
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[*] posted on 23-6-2024 at 13:44


The acidity of the acid itself may contribute to instability (the free H+). Or, since the main decomposition pathway of energetics is based on BDEs (bond disassociation energies) of different groups and bonds on a molecule, if the oxoacid has a lower BDE than other groups in the complex (ionic bonds between the metal and anion), it could kickstart a decomposition process. C, O, and N intermediates may also simply be easier for a group like ClO4-, NO3-, etc to oxidize than the metal itself too. OB% factors in to this as well, along with perhaps higher densities of the materials due to packing of the nitrogenous oxoacids in the complex’s lattice; such higher densities can affect sensitivity too.
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[*] posted on 30-6-2024 at 05:24


Can hexamine undergo hydrolysis with sodium hydroxide to form sodium formate, ammonia and methanol?
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dettoo456
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[*] posted on 3-7-2024 at 17:56


It’d likely form ammonia (or more likely urea) and formaldehyde (the formaldehyde quickly decomposing to formate), in a reverse reaction to the manner in which hexamine itself is prepared.

A controlled hydrolysis may yield (mono, di, or tri)methylamine.

I doubt the conditions would be anywhere close to reducing enough to reduce formaldehyde or formate to methanol.

[Edited on 4-7-2024 by dettoo456]
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solo
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[*] posted on 4-7-2024 at 16:03


..how to mono aminate 1,5-Dibromopentane....solo





It's better to die on your feet, than live on your knees....Emiliano Zapata.
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dettoo456
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[*] posted on 16-7-2024 at 17:16


Explosion welding/cladding is usually carried out on thin metal sheeting (no greater than 1” or 25mm) with minimal explosive used per sq in (<50g in most cases, and low power EMs like ANFO at that).

Would there be any way to feasibly weld 2” (50mm) or thicker mild steel with much larger quantities of explosive or higher VoD explosives?

As the size of the EM charge itself is increased, I’d assume a kicker charge design might be able to increase the total energy transferred to the witness plate from the flyer plate. But as the EM performance rises, and brisance along with it, I’d be worried about the flyer plate just being shattered or shock hardening to the point that it’d be too brittle to weld to the witness.

For context, I have lot of thick steel bar scrap and am too cheap to buy an anvil.
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