LifeisElemental - 27-10-2015 at 14:42
Hi all,
I made a video on the synthesis of 4-nitroaniline to introduce basic concepts of organic chemistry to students I tutor.
https://www.youtube.com/watch?v=O__IggS1fjc
Does anyone have any thoughts as to why it caught fire as the column grew? I have never seen this happen before. Also would look forward to any
feedback on the video itself
Thanks
RareEarth - 27-10-2015 at 16:34
You have an awesome camera. Good video editing as well. Can I ask what kind of camera you use?
Don't know the specific answer to your question, but just some ideas... maybe your reagent melted, a tiny bit vaporized, and ignited with the flame,
linking back up to the column? Perhaps even some residual nitric acid. It's hard to know for sure when working with open flames.
[Edited on 28-10-2015 by RareEarth]
LifeisElemental - 28-10-2015 at 12:39
Thanks! It is a Canon 6D camera. Edited in after effects and premiere.
aga - 28-10-2015 at 13:27
As far as i have seen/read, the p-nitroaniline + sulphuric reaction is touchy as regards purity and proportions.
Get it right, and it's a Long carbon thing.
Get it wrong and there's just bits of carbon ejected everywhere.
In the middle there's a flaming black phallus, which is what the video shows.
The Quality of the video and the production are excellent.
Very close to professional grade IMHO.
Scripting may need a bit of work (to get to perfection) however very very good indeed !
clearly_not_atara - 30-10-2015 at 11:49
To me it looks like the acetanilide partially cleaved or may have undergone a Fries-like rearrangement to lose the acetyl group. Once free aniline is
generated the reaction between this and nitric acid is highly exothermic. There's also the possibility of radical decomposition via
N-nitroso-acetanilide.
For a milder reaction, consider the Ullmann-Goldberg reaction between p-chloronitrobenzene and acetamide or urethane catalyzed by copper salts. This
generates the desired p-nitroacetanilide rather smoothly. P-nitrochlorobenzene might also he converted to the fluoride at high temperature; the
fluoride should react with ammonia directly.