Enneaheptite heptanitrate - a good impro. alternative to PETN?

[Mr Cool]

Enneaheptite is made in a very similar method to PE. Instead of 1 mole of acetaldehyde, 4 moles of formaldehyde and 1 mole of NaOH, use 1 mole of acetone, 7 moles of formaldehyde (in aqueous soln.) and 1 mole of NaOH. These substances are easy to find, whereas acetaldehyde is not...
Enneaheptite has the following formula: (HOCH2)3C-CHOH-C(CH2OH)3 (found on wantsomfets page, in an article about PETN by Naoum). It's heptanitrate would be very powerful, almost as stable as PETN, but probably a bit more sensitive.

Has anyone found any other texts describing this compound? I'm trying to find out why it hasn't been used - I'm guessing that it's more expensive and more sensitive than PETN, but neither of those disadvantages is very bad for us. I'm going to buy some acetone today and try to make it...

I've also heard of anhydroenneaheptite, which is a cyclic compound formed by dehydration of enneaheptite, so that the two ends of the molecule are linked together by an oxygen atom, and 1 molecule of water is lost.

[Madog555]

sounds very interesting, does anybody know anything about the preperation of formaldehyde?

[Mr Cool]

It can be bought as a disinfectant if you can't get it from a chemical supplier - check out suppliers for farms, they often sell it (both c. 35% soln. and paraformaldehyde). Or it can be made by the hydrolysis of hexamine with an acid, such as HCl or HNO3 - if you ever leave hexamine dinitrate damp in a sealed container and open it after a few days, there will be a very definite smell of CH2O. If you heat it CH2O will be produced quite fast (heat it in solution, not solid form...).

Damn, no-where selling acetone near me is open on a Sunday. Maybe tomorrow...

[Lagen]

I have found a synthesis for anhydro-enneaheptite, which actually uses 1 mole acetone, 8 moles HCHO and 0.9 mole Ca(OH)2. I'd rather use Ca(OH)2, as NaOH would be difficult to remove, maybe the enneaheptite could be ppted out, but - there is almost no information available on enneaheptite, let alone its solubility in various solvents... This is the "cold, slow" method, so maybe if you were about to reflux the mixture you would use 1 mole acetone to 7 moles HCHO as some of the acetone would escape.

I will try to translate the article and put any blurb I have on this up on my site.

Yes, looks like a good choice of explosive.
Easy to make from scratch? - Yes.
More expensive? - On a home preparation scale probably not, because of the extreme prices of acetaldehyde at chem suppliers.
More sensitive? - Probably not on the order of primaries, meaning: Easier to detonate!

I think making the heptanitrate won't be feasible though - I have seen no synthesis for free enneaheptite, just the cyclic anhydride. Two alcoholic groups are lost here, and not available for nitration (well, nitro-esterification...) A patent I found mentions just enneaheptite pentanitrate.

[Mr Cool]

The file on wantsomfet's page definitely shows it as a straight chain, and calls it enneaheptite. Both probably exist I think, the principal product depending on the reaction conditions maybe?

It also gives this reference: "For the similar synthesis of enneaheptite from acetone and formaldehyde by water and slaked lime see Tollens; Ann. 289, page 47.'8".

I'm trying the reaction now, I just threw everything into a bottle and sealed it - the "cold, slow" method!

[wantsomfet]

According to the german patent 28657 (1913) anhydroenneaheptite pentanitrate is slightly more brisant than PETN and considerably less sensitive to mechanical initiation (2kg weight drop test: 30cm, PETN 16cm).
It requires lots of nitrating acid to get the pentanitrate, 20 parts mixed acid (20% HNO3, 80% H2SO4) per part anhydroenneaheptite. Nitration temp. never above 25°C - 27°C.
I'm sure i have also something about enneaheptite, if i find it i'll post it...

[Lagen]

Mr Cool - the ref. actually contains a synth for anhydro enneaheptite, it's on my site. The article contains some analysis desriptions, that prove this - I left them out, but when I have some time I'll translate them as well, it's 4 pages. I couldn't find any other ref. so far, and all the organic chemists seem not to have heard of the stuff.

[Mr Cool]

Mixed acid can be used! That's good, it makes it simpler than distilling HNO3. I wonder if v.conc. HNO3 is better though - it is for PETN.
That's not really very much acid - 1g of AEH only requires c. 9mL of H2SO4 and c. 3mL of HNO3. Although that is something like a 100% excess of HNO3 I think (too tired to check...). Still, it could be worse.

More brisant than PETN, eh? This is sounding better and better...

[Mr Cool]

Hmmm... it seems the "cold, slow" method might not be so cold at all.
Like I said, I threw it all in a bottle and screwed the lid on. 105g paraformaldehyde, 30g acetone and 20g Ca(OH)2, c. 750mL of water in total. I then just kinda forgot about it.
I checked on it today, it has gone dark brown (decolourising charcoal will be needed...), and when I opened it a large amount of air hissed into the bottle. The only reason I can think of for so much air getting sucked in is that the reaction got hot, and forced air out through the imperfect seal. The bottle then cooled, but for some reason the air did not all get sucked back in, so a low pressure was created. It must have got pretty hot...
So if you do this, keep an eye on it.

[nbk2000]

If there's a creek nearby, you could put in there to keep it cooled as long as neccessary. Just have a vent tube to release any pressure.

I wonder if you could use NO3/H2SO4 with this instead of mixed acid?

[Mr Cool]

I'm getting pissed off now. I don't think this stuff likes me - it's refusing to crystalise. But the evapourated soln. is very thick, there's definitely some in there.

[kingspaz]

i think any reaction that requires a mixed acid bath can be performed with xNO3 + H2SO4 since HNO3 is yielded upon addition ot the acid. :)

[drstrangelove]

On the subject of formaldehyde,I have seen it for sale as "Portable toilet cleaner",but the bottle is one litre and on the packaging it says contains 250ml formaldhyde-about $10 a bottle-I am unsure what else it contains-beware there are also non toxic toilet cleaners around which contain no formaldehyde.

[kingspaz]

Mr cool, have you had any success separating it? is this explosive toxic?....maybe somthing to keep in mind if it is....

[Pu239 Stuchtiger]

It is most likely that the 750mL of the mystery ingredient is water.

[dave]

I just found this topic and it looks pretty interesting. All the chemicals are within my limited reach. Has anyone made any progress on synthesis of enneaheptite? It has been almost 1 year since the last post and it seems like the posting just stopped. Mr. Cool how did the synthesis go? Did you ever extract anything?

[Mr Cool]

I can't remember how it went now :(. But it definitely never went very well, if it did then I would have used it more and therefore I wouldn't have forgotten about it!
Have a go if you can, but if I were you I'd add the formaldehyde quite slowly to avoid it getting too hot because this can cause problems.
Also, from what I read it sounds like the stuff is very hard to get to crystalise - it likes to form super-saturated syrups.