gl92038
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What could it be
Hello, I have some strange compound, which I synthesised by following steps:
1) I mixed 5 grams of Benzoic acid with 5 grams of thionyl chloride( I expected to produce benzoyl chloride, but almost nothing happened when I mixed
the compounds)
2) I added 3 grams of Ethanolamine( Apparently It was technical-grade, because It was not colorless as described on wikipedia)
I expected to get dibenzoyl (2-hydroxy ethyl) amine
The exothermic reaction proceeded and I was left some solid brown compound, which is soluble in water, and has the strong offensive smell...
What could it possibly be?
Thanks for any help 
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GreenD
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I mixed 5 grams of Benzoic acid with 5 grams of thionyl chloride
in what solvent? or did you do it neat?
I'm not sure but I'm guessing you probably got some polymerizations of ethanolamine.
amines have strong smells... does it smell like dead fish, cheetos, or smelly salami?
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gl92038
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I mixed them without any solvent.
Why would polymerization happen?
But It smelled really nasty.
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Dr.Bob
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How long dis you mix them? Did you add an excess of thionyl chloride? They are slow to react, and normally I would stir them overnight or reflux
them to get the acid chloride reaction to go to completion. Then you have to evaporate off the excess thionyl chloride (usually chase it off with
toluene or another solvent) to get pure acid chloride which can then be reacted with an amine. You will also need some triethylamine or other base
to absorb the HCl, or it will make the salt of the amine, which is non-reactive. And some DMAP or other catalyst will likely speed up that reaction,
which would work best in DCM or pyridine, but many solvents will work for that.
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Paddywhacker
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If you mixed ethanolamine with thionyl chloride then you could well have 2-chloroethylamine, which I would expect to be a real nasty compound.
However it would be present as the nonvolatile hydrochloride salt in solution, so it is unlikely to be that which you smell.
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gl92038
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Actually I mixed them for 10 minutes. I know it was not even close to be enough.
Well, when i mixed ethanolamine with thionyl chloride nothing happened. And I don't expect benzoic acid to react with ethanolamine.
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woelen
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Be very careful with what you are doing there. If you have ethanolamine and you replace the hydroxyl groups with chloride, then you get very nasty
blister agents. The worst one is with triethanolamine, but I'm quite sure that the monoethanolamine also gives a VERY nasty compound.
Some amines have a very exothermic reaction with thionyl chloride (e.g. triethylamine, mixed with thionyl chloride leads to a loud crackling noise
when mixed and instant charring of the organic compound). So, before you mix stuff, be sure to use very small quantities, or use an inert solvent,
just to be sure that there are no bad surprises for you.
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Perdurabo
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The use of a solvent is generally preferred. Not only does the solvent allow more efficient physical interaction of the reagents, it will also help
to dissipate the heat of reaction, making the whole process safer
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