JJay
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Diethylamine from Deet
After a recent de-acetylation of acetaminophen failed, I started wondering about amide hydrolysis more generally... I have a bottle of 100% DEET
sitting on the shelf, and it looks pretty easy to hydrolize... I guess a reflux in ethanol / potassium hydroxide followed by fractional distillation
would do the trick?
Does law enforcement care about diethylamine these days? I had thought it was DEA List One, but it is merely a Special Surveillance chemical...
Does anyone know what reaction conditions would be required for the hydrolysis? I was thinking something like mix 45% DEET, 45% ethanol, 10% KOH, and
reflux for an hour, but I am not very experienced at guessing these....
What interesting things can be done with dyethylamine? Am I correct in assuming that it smells like rotten fish?
[Edited on 23-2-2017 by JJay]
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JJay
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Oh and also, what could I do with m-methylbenzoic acid besides make toluene?
[Edited on 23-2-2017 by JJay]
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Corrosive Joeseph
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Cool idea............ I've been wondering about amide hydrolysis myself this week, but not on this particular substrate.............
Here's a bunch of information but you'll have to sort through it. I'm sure you find some parameters and a decent working procedure out of all
that..............
DEET - https://en.wikipedia.org/wiki/DEET
Amide Hydrolysis - http://www.chemguide.co.uk/organicprops/amides/hydrolysis.ht...
Snippets :
Acid Hydrolysis - https://www.thevespiary.org/rhodium/Rhodium/Vespiary/talk/in...
Base Hydrolysis - https://www.thevespiary.org/rhodium/Rhodium/Vespiary/talk/in...
More Snippets - https://www.thevespiary.org/rhodium/Rhodium/Vespiary/talk/in...
And - https://www.thevespiary.org/rhodium/Rhodium/Vespiary/talk/in...
From SM :
OTC Diethylamine, the easy way
http://www.sciencemadness.org/talk/viewthread.php?tid=954
Diethylamine Synthesis thread (11 pages)
http://www.sciencemadness.org/talk/viewthread.php?tid=11081
Diethylamine Hydrochloride Synthesis
http://www.sciencemadness.org/talk/viewthread.php?tid=24131
Storing Diethylamine??
https://www.sciencemadness.org/whisper/viewthread.php?action...
/CJ
[Edited on 23-2-2017 by Corrosive Joeseph]
Attachment: Hydrolysis of Amides.pdf (238kB)
This file has been downloaded 611 times
[Edited on 23-2-2017 by Corrosive Joeseph]
[Edited on 23-2-2017 by Corrosive Joeseph]
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JJay
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These are actually helpful links. Reading through these threads (not all of which came up when I searched on this topic previously), it looks as
though madscientist proposed using similar reaction conditions, which were eventually tried by ScienceSquirrel, who also tried using ethylene glycol
as the solvent. The conclusion was that detectable amounts of amine were formed in an hour but that long reflux times were necessary to achieve good
yields.
S.C. Wack mentioned an experiment under more dilute conditions using ethylene glycol as the solvent, resulting in a measurable amount of the product:
http://www.sciencemadness.org/talk/viewthread.php?tid=11081&...
There are some other reports that suggest carrying out the reaction in a sealed media bottle in a water bath or in sulfuric acid, but S.C. Wack's
appears to be the most credible.
Assuming that the hydrolysis is not reversible (I don't think it is), it looks like it would take 12-13 hours for the reaction to go 90% to
completion. 24 hours should be plenty.
Since the product is volatile, it's probably a good idea to run the reflux condenser output through a dilute acid (with an appropriate suckback trap)
if running a long reflux.
I'm thinking about giving this a try, but if I do, what should I do with the DEA afterwards? 
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Tsjerk
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In theory that sounds like the perfect way to push the reaction forward and monitor its progress at the same time!
Ethylene glycol boils so high that in basic conditions all diethylamine will immediately boil off. The gas you can catch in HCl, weight of the acid is
the indicator of the progress.
Just keep in mind that as there is no water present you need at least an stoichiometric amount of KOH (or am I crazy? I just wrote down the equations
which show it is not a catalyst...).
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JJay
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I'm pretty sure there will be some water in the KOH, which I think should be present in excess. I don't see why water would be necessary in more than
catalytic amounts if doing a base hydrolysis with a hydroxide, but I'm certainly not about to call you crazy.
I was thinking about catching the DEA with hydriodic acid just because it would be hilarious to have a bottle labeled DEA HI  But HCl is certainly more practical, and I don't have any hydriodic acid, of course
(though it does look easy to make). I remember seeing some practical reason for making DEA oxylate....
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Tsjerk
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Hydroxide reacts one on one with DEET, and if you would do 45/45/10 you wouldn't have enough, no matter if there is water in the KOH or not.
Edit: I like HI*DEA haha
[Edited on 23-2-2017 by Tsjerk]
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JJay
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Quote: Originally posted by S.C. Wack  |
Using only 11 g. KOH, 4.25 g. DEET, 100 ml. ethylene glycol, 8 g. water, and 2 hours at 140C, there was obtained, with little care in the isolation, a
33% yield of snow white recrystallized toluic acid crystals. The purity is likely pretty good given the massive disparity in solubility in hot vs.
cold water. I suspect that the missing yield has little to do with unreacted material, even though the amine (as the hydrobromide, for hahas) was
isolated in even lower yield, 19%, from recrystallization in IPA/toluene.
[Edited on 2-9-2008 by S.C. Wack] |
Actually, reading over this a little more closely, perhaps the reaction time can be considerably shorter than 24 hours.
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JJay
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| Quote: Originally posted by Tsjerk | Hydroxide reacts one on one with DEET, and if you would do 45/45/10 you wouldn't have enough, no matter if there is water in the KOH or not.
Edit: I like HI*DEA haha
[Edited on 23-2-2017 by Tsjerk] |
You're right!
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MrHomeScientist
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I looked into this at one point too, to make a thermochromic compound at home. I did try it at work where I had the materials available: https://www.sciencemadness.org/whisper/viewthread.php?tid=30...
I didn't have too much success, but maybe you can do better!
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Tsjerk
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btw: I don't think your glassware is going to like KOH in ethylene glycol at its boiling point, I guess a water at 90 degrees should be enough for
this reaction.
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JJay
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| Quote: Originally posted by Tsjerk | | btw: I don't think your glassware is going to like KOH in ethylene glycol at its boiling point, I guess a water at 90 degrees should be enough for
this reaction. |
It looks like I'll just need a cheap Erlenmeyer, a rubber stopper with a hole in it, and an oil bath with a candy thermometer. I can run any gaseous
products through gas washing bottles filled with dilute HCl or a distillation apparatus. I only have Dreschel bottles, but I sure wish I had some of
these!
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Tsjerk
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The boiling point of diethylamine is around 55 degrees Celsius, so it should also condense while bubbling through the acid, I think the absorption
will be OK.
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JJay
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| Quote: Originally posted by Tsjerk | | The boiling point of diethylamine is around 55 degrees Celsius, so it should also condense while bubbling through the acid, I think the absorption
will be OK. |
I think so too, but I can use a high-efficiency condenser just in case. I think I might actually give this a try after I get some propylene glycol. I
have some glycerol....
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