zeppelin69 - 18-9-2009 at 08:58
This experiment started as an attempt to make tetranitronaphthalene, which I quickly discovered was not as straight forward as I had imagined. Without
doing much research, I began the experiment the same way I would have for making trinitrotoluene, which I have done numerous times.
Finely powdered naphthalene was added to a sulfuric acid / ammonium nitrate mixture at about 40*C. To my surprise the naphthalene was quickly
oxidized, releasing NOx fumes much like if ASA is added to a sulfuric acid / nitrate salt solution. I decided that maybe it would be better to add the
naphthalene to the sulfuric acid first, then mix in the nitrate, but this was actually worse than the first attempt.
Then I had the idea of using much weaker acid, so I dusted off my old bottle of 40% and added the nitrate then the naphthalene to it. When nothing
happened, I was disapointed but not really surprised. So I called it a night and I left the mixture the magnetic stirrer.
The next morning, I was thrilled to see the naphthalene had become very pale yellow randomly shaped crystals. I put the beaker on a hot plate for a
few hours to see if I could coax any more of a reaction out of it. Around 80*C the crystals melted into a pink oil that floated on top of the
nitration mixture, I moved the beaker back to the stirrer and let it cool down. This time it formed more intensely yellow, needle shaped crystals
similar to other nitroaromatics.
I estimated that this was probably mononitronaphthalene, so I filtered the crystals and added them to another sulfuric/nitrate mixture, this time
using 70% sulfuric acid. Using this solution, I repeated the same method I used earlier of heating for a few hours, then cooling on the stirrer, and I
observed two more changes in the naphthalene. The first was a dark red liquid, which I realized probably wasn't the dinitro, but I kept reacting
anyway just to see where this would take me. After a while, the red liquid crystallized into dark red octagonal shapes, that I thought ironically
looked like stop signs about 5-6mm across.
I decided to push further, so the crystals were filtered and then added to a proper 98% sulfuric acid/nitrate salt mix, which completely oxidized my
product just as it had in the beginning. Intrigued, I decided to run the whole experiment over again. All the steps proceeded the same as before, but
when I arrived at the octagonal crystals I decided to neutralize, recrystallize and save my product.
It seemed that the sodium carbonate I was using to neutralize my product somehow began oxidizing it, turning some of my crystals into a nasty tar! I
filtered out the remaining crystals (tar included) and decided to just proceed with the recrystallization, ethanol being my solvent of choice. After
boiling, then cooling, very fine yellow needles formed, but it seems as if the ethanol may have somehow reacted with my product forming a complex of
some kind. I say that because the mass of the crystals is now much greater than before and most of the ethanol was gone upon cooling. I only have one
picture, and it is of the recrystallize product. Does anyone have any idea what is going on??
You can see a bit of the tar that made it through the recrystallization. The red liquid is the remaining ethanol. Other things I have noticed is that
the product is a yellow dye similar to picric acid, and it is very slightly soluble in water as well.
hissingnoise - 18-9-2009 at 11:53
Tetranitronaphthalene seems somewhat unattractive from a synthesis and performance standpoint, but if you're intent on producing it, try it with mixed
acid or Na or K nitrates; NH4 may have reacted with the naphthalene and complicated your synth. . .
You could also have a look at what Davis has to say about it in COPAE!
hissingnoise - 18-9-2009 at 12:05
Your product, BTW, looks delicious (strawberries?) and with the ethanol and the almond smell it'd be very tempting to any small child. . .
Paddywhacker - 18-9-2009 at 13:39
Time to try some chromatography. Use blotting paper if you can't get anything better. Gives you a better idea of your reaction progress.
zed - 19-9-2009 at 00:18
Me, I'm a nervous type. The idea of performing a nitration, wherein I'm not sure what product I have created.......It gives me the heebee jeebees.
JohnWW - 19-9-2009 at 00:51
Is the stuff of any use as an explosive? Another use for it would be to reduce it to naphthalene tetraamine, which could be reacted to form other
amine derivatives.
hissingnoise - 19-9-2009 at 06:24
It seems the final nitrating step requires anhydrous mixed acid and high temperature; the compound itself is as powerful as TNT but less sensitive,
probably needing a booster for certain detonation. . .
I think it saw limited use in the 'Great War' in some propellants!
zeppelin69 - 22-9-2009 at 04:57
Im not actually interested in using the explosive properties of TeNN, it's more of a novelty thing. I have a bit of a collection of small amounts of
different compounds going and this is just one more I'd like to add to it.
Paddywhacker, I like the idea of chromatography but I'm not sure how it can help me here. I am almost certain that I do not have TeNN, correct me if
I'm wrong but there is no real way to use chromatography to identify an unknown compound is there?
Zed, I may not be as paranoid as I should be, but I am wearing gloves and being extra cautious with handling it because I dont know what it is.
I suppose I'll keep this "stuff" around for a while longer to try to figure out exactly what it is. Next time I shoot for TeNN though I'll be sure to
use alkali nitrates instead, and post back with what I find. Thanks guys!
Paddywhacker - 22-9-2009 at 14:11
With chromatography you can follow the reaction sequence.
So early on you might see two isomeric nitrates and then later on see more bands. So you can tell the early precursors from the late. And among the
late products you any TeNN would show as a new band that gets stronger over time.
Also, paper chromatography can be used for micro-scale preparation. You can cut out and extract individual bands, and then see what you get when you
nitrate those.
You are right, though, that you can't really use chromatography to identify products without having pure compounds for reference. But as I pointed
out, using experimentation and logic you can get most of the way there.