Tdep - 19-11-2017 at 22:37
So a bit of context to this question.
Back in late 2015 I ran some 5-ATZ from the diazionation of aminoguanidine bicarbonate as written up by Engager. I would always get this weird yellow
precipitate that i'd remove then continue on with the synthesis, all of which failed. Once or twice I ended up purifying soldium sulfate out of the
reaction mix, getting excited about my yields and how good the crystals looked... very sad moments.
Fast forward to this year and I tried it again, got the same results and with the help of my uni's NMR I confirmed that the yellow precipitate was
indeed the 5-ATZ, and there was no obvious contaminate that was making it yellow, the 1H NMR and 13C NMR was clean. This is all in a video I made
recently here: https://youtu.be/4Q4jU-J3mKg
Sure, that's all fine. But somehow, i'd managed to keep the yellow precipitates from back in 2015! More 5-ATZ just lying around under my nose this
whole time! I show the old precipitates in the video at 14:16
I recrystallised this from water, washed with ice cold water and a little bit of methanol (bad move, this dissolved quite a bit of it) but then on
drying... this stuff isn't 5-ATZ.
5-ATZ melts and then burns on heating, as far as i'm aware. This is what the recently synthesised batch does. The newly recovered stuff just blows up.
It undergoes DDT in very small amount. While not insanely powerful, I haven't seen this level of DDT outside of a heavy metal salt (I haven't done
much tetrazole stuff yet).
VIDEO: https://youtu.be/CtncHnT5G7w
If it's not 5-ATZ, what is it? Did storing it slightly damp for nearly 2 years cause it to change? Could it have been something else the whole time...
the diazonium intermediate? Nah, i've isolated that before I believe and it didn't do what this stuff does. So any ideas?
I should mention its the same colour as my 5-ATZ sample, so I fully expected it to be 5-ATZ until it exploded. I have approx 80mg I think after the
recryst. Glad I don't have more or things might've got hairy...
It's also acidic so I don't believe it is a salt of any kind, it is a free acid tetrazole.
Thanks for your thoughts
tl;dr: I recovered what I thought was 5-ATZ, but instead of melting and burning it easily undergoes DDT, but i'm not sure what it is.
Rhodanide - 20-11-2017 at 05:49
Dissolve it in water and feed it to your Epazote plants - make Supazotes 
The Volatile Chemist - 20-11-2017 at 10:17
I don't suppose you've got access to your uni NMR, since you've graduated now, right?
nitro-genes - 20-11-2017 at 12:10
It's makes DDT too quick to be tetrazene or MTX-1, which was my first guess...hmmm... guanylazide itself? Maybe nitrotetrazole, a diazotization
product of diaminoguandine or some guanazole derivative? Could be a lot of things probably.
[Edited on 20-11-2017 by nitro-genes]
NeonPulse - 20-11-2017 at 17:11
Very interesting! Did you make the original batch with nitric acid? Perhaps while storing it wet and with residual nitric left it created
nitrotetrazole of sorts over time. I was also going to guess tetrazene at first but as nitrogenes above said it undergoes DDT too fast. Did you try
mix it with silver nitrate in minute amount and see if you get a result.
Tdep - 24-11-2017 at 05:06
I don't have access to the NMR anymore no, which is sad.
I didn't believe I had made it with nitric acid, but I went back and checked the footage and surprisingly, I had used nitric acid for the final acid
pH adjustment to 4 for tetrazole crystallisation! (This was to avoid crystallisation of sodium sulfate)
So it was stored damp with nitric acid for 2 years... So nitrotetrazole is my current theory too. Given the high acidity of the product as well. Any
specific tests? It's quite interesting that nitrotetrazole appears to have formed this way, this hasn't previously been reported in the literature I'm
sure
Dornier 335A - 26-11-2017 at 14:21
5-Nitrotetrazole is extremely hygroscopic so that should be a clue. I dried mine over conc. sulfuric acid for a few weeks and got crystals, but they
turned into puddles in less than five minutes after I opened my desiccator. My first thought was that it might be something like
5,5'-diazoaminotetrazole or azotetrazole. Both form from oxidation of 5-ATZ followed by condensation with another 5-ATZ. The latter even decomposes to
5-azidotetrazole in contact with nitric acid.