Hi all, last night I thought I'd try making Aniline Nitrate by addition of Aniline to concentrated HNO3. My Aniline is a few months old,
and therefore orange. Upon addition of Aniline to a roughly 50% solution of HNO3 in water, I was left with a clear solution, and no
crystals like I was expecting. I added roughly 10mLs of WFNA to the solution, which formed an intermediate, blue oxidized Aniline compound. Upon
addition of 2 more mLs of Aniline, I got a nice thick crop of red crystals, which I vacuum filtered. According to the synthesis, I should have just
gotten colorless Aniline Nitrate when the two initial reactants were combined. Instead, I had to modify the synth to get any precipitate. Also, why is
my precipitate red? A strongly-colored byproduct?
I'm a bit confused.
Thanks,
-R/T
P.S. I got the synthesis from the PrepChem synthesis of Diazobenzene Nitrate.
[Edited on 18-12-2017 by Tetra]PirateDocBrown - 18-12-2017 at 06:33
Never add aniline to any sort of nitric acid. You are lucky you didn't blow yourself up.
Your dilution and the possible degradation of your reagent are likely the only things that saved you.
Aniline and WFNA are hypergolic, and detonate on contact.
Never add aniline to any sort of nitric acid. You are lucky you didn't blow yourself up.
Your dilution and the possible degradation of your reagent are likely the only things that saved you.
Aniline and WFNA are hypergolic, and detonate on contact.
[Edited on 12/18/17 by PirateDocBrown]
I don't ever plan on trying that. However, my Nitric acid was 50% at first, so the WFNA only added to that. I didn't START with WFNA. unionised - 18-12-2017 at 10:18
I remember one of our Organic chem lecturers explaining that, if you want to nitrate aniline you need to acetylate it first ( or something). His
comment was that without that first step you either got a fire, or "road mending material."
I doubt aniline forms a stable nitrate (and I'm using a pretty loose definition of "stable")Rhodanide - 19-12-2017 at 06:19
I remember one of our Organic chem lecturers explaining that, if you want to nitrate aniline you need to acetylate it first ( or something). His
comment was that without that first step you either got a fire, or "road mending material."
I doubt aniline forms a stable nitrate (and I'm using a pretty loose definition of "stable")
Bitumen: Now with Aniline Nitrate!
But really, when they say that in the synthesis that you're supposed to get a white precipitate, are they just taking the piss or is it actually
possible?Bert - 19-12-2017 at 08:55
You have fuming nitric acid? So try nitration of dimethylanaline instead. Tetryl is more fun.
I do not have Dimethylaniline.
As for the WFNA, I don't see what all the confusion is about.
Firstly, I DID NOT start with pure WFNA. Aniline was added to FIFTY PERCENT (50%) Nitric acid. ONLY AFTER, was a small
splash of WFNA added to the solution of Aniline Nitrate, to increase the acid concentration. After that, there was only slight exotherm,
but no more than adding NaOH to water.
Hope this clears things up, and no, I know damn well enough not to add a fuel, an Amine even, to WFNA. I don't have a death wish, hahaha. Bert - 19-12-2017 at 13:22
Quote:
I do not have Dimethylaniline.
You have analine. Do you have methanol and sulfuric acid?
Quote:
As for the WFNA, I don't see what all the confusion is about.
There's a slight confusion here. You are trying to make aniline nitrate the salt (PhNH3+NO3-), not to
nitrate aniline.
The reason why you did not observe any product is very likely down to solubility. Aniline surely gets protonated, it's just that the solubility limit
of aniline nitrate was not reached and the salt did not crash out. Actually aniline nitrate is very soluble in water! Cool the solution down and see
if you get any crystallization, if not, increase the aniline concentration. Do not try to evaporate the solution to dryness, heating a mixture like
this can easily lead to a severe runaway. I would also go for a smaller scale just in case.
[Edited on 23-12-2017 by kavu]Bert - 23-12-2017 at 08:33
May I ask why you are interested in aniline nitrate, I do find some references to this in older books on dye chemistry.
unionised - 23-12-2017 at 09:48
It should be possible to make it
"The crystals of anilinium nitrate, C6H8N+·NO3−, were obtained by slow evaporation of an aqueous solution. " https://www.researchgate.net/publication/233851807_Structura...
but I doubt it's very stable.
This is interesting (and quite pretty)
shodhganga.inflibnet.ac.in/bitstream/10603/86766/17/17_chapter%208.pdf clearly_not_atara - 23-12-2017 at 10:16
I think that rather than using nitric acid, salt metathesis of aniline sulfate with calcium nitrate should prevent redox and nitration reactions even
at high concentration. thehexlibrary - 16-5-2020 at 16:56
Whassup man!
I wish I could say this with more specificity, but I'm pretty sure what happened is you oxidized the aniline to a Dye of the Induline Class. Check out
this wiki page https://en.wikipedia.org/wiki/"Induline Induline is a dye of blue, bluish-red or black shades.[1] Induline consists of a mixture of
several intensely colored species, so the name is often indulines"
The Indulines are usually hard to seperate from each other, and don't make the greatest dyes, therefore were never of commercial importance, like
Rosaniline, Muave, etc. There's also alot of indulines so its hard to pinpoint the ones you likely made.
I believe you made aniline nitrate with the 50% HNO3, but when you added the WFNA, it oxidized the aniline instead to an induline. (See the attached
picture of induline.. its basically a ton of anilines attached). Also in my experience indulines often start blue but then turn red.
Rhod love ur vidoes brotha!
-Nick
Youtube: Thehexlibrary23