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woelen
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Klute, for me this experiment with thionyl chloride and MeOH is purely an academic thing, and this discussion on its own already is a pleasure to read
(also thnaks to Nicodems very nice contribution). But I certainly will try the MeBr thing as well.
I have the thionyl chloride from a German supplier, who is geared towards the hobby market and sells and ships many fantastic chems to private
individuals in the EU (unfortunately no TCT, but he does sell all common ...yl chlorides like SOCl2, SO2Cl2, C6H5COCl, CH3COCl and even (COCl)2, I
purchased all of these, except the oxalyl stuff, that is too hefty for me). For more info, please U2U, I don't post such sources here, because k3wls
are reading this also.
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chemrox
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The reaction of alcohols and thionyl chloride in the presence of pyridine is a known (literature) procedure. It is even named. It is called,
"Darzen's procedure." Why one would omit the pyridine puzzles me. Anyway, you've proved the necessity of the pyridine. Thanks for the spec. How
did you manage to paste it like that and make it fit so well?
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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Sauron
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I'm sure other appropriate tertiary amines would do just as well as pyridine. Diethylaniline is often mentioned in the lit. in this contest, because
its hydrochloride (unlike that of pyridine) is easily filtered and is non-hygroscopic.
Another obvious alternative is TEA (triethylamine).
Sic gorgeamus a los subjectatus nunc.
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woelen
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I just tried the reaction between triethylamine and thionyl chloride, moderated by diluting it 20 times with DCM. If I mix these two dilute solutions
in DCM, then immediately after mixing, the liquid becomes yellow, and from that moment on, it fairly quickly turns darker and darker. One minute after
mixing, the liquid is totally black and turbid and slightly warmer (35 C or so).
Mixing the pure triethylamine and thionyl chloride results in a very violent reaction with formation of a black solid (I described it earlier in the
thread). But apparently the dilute material also produces this black compound at room temperature. So, the black material most likely is not carbon.
What could this dark compound be?
If I mix methanol with DCM, and also add a little amount of triethylamine and add a solution of thionyl chloride in DCM to this, then the liquid
remains clear and colorless, and there is occasional bumping, when gas is produced in large bubbles.
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I also did a related experiment, adding a few drops of pure acetyl chloride to pure methanol. When this is done, then each time when a drop of acetyl
chloride falls into the methanol, there is a little explosion. After a few drops, the test tube was cracked. Next time, I'll use a thick-walled test
tube. A fruity smell was produced (methyl acetate I assume).
I am really impressed by the violence of the reaction of the acyl chlorides with methanol. The reaction is MUCH more violent than with water.
It is time for me to get more DCM, the reactions with the pure compounds simply are too violent to be of any practical use 
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kmno4
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| Quote: | Originally posted by woelen
Mixing the pure triethylamine and thionyl chloride results in a very violent reaction with formation of a black solid (I described it earlier in the
thread). But apparently the dilute material also produces this black compound at room temperature. So, the black material most likely is not carbon.
What could this dark compound be?
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It is can be some kind of plymer. Such polymers are mentioned for reaction SOCl2 with NH3 in paper 10.1021/ic50167a050 (and reference number 3[from
Berichte der deutschen chemischen Gesellschaft]). Other amines propably give similar reactions.
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