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Sauron
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We've posted quite a number of different articles on the forum in different threads, use Search and download the files pls.
However I can summarize the different TCT to acyl chloride processes as follows:
1. (old) applicable to acetic acid and other liquid acids.
Relux TCT with a large excess of acid until no more insoluble cyanuric acid precipitates. Filter off the cyanuric acid byproduct and wash with some of
starting acid. Combine washing with filtrate and distill the acid chloride from the unreacted starting acid.
2. (old) Dry distill sodium salt of acid with small excess of CC.
3. To a solution of the acid TEA in acetone add CC in acetone and stir at RT 4 hours. Cyanuric acid ppts out. Filter. What remains is a mixture of
acid chloride, unreacted acid, and TEA in acetone. Rotavap off the acetone bubble in dry HCl to ppt out the TEA as hydrochloride, filter, distill. See
article for molar ratios.
4. Form TCT/DMF comples, react this with acid. See article for workup.
The first two procedures are perhaps best for larger scale preps.
The third prep is designed for convenience especially if you want to use the acyl chloride in situ, many examples are given of this.
The fourth is very efficient and high yielding.
How much propionyl chloride do you ant to make?
Here's a zip file, there's the main TCT/DMF article, plus a Brazilian review, and a JACS piece on using TCT (CC) to make alkyl chlorides from
alcohols.
I am still hunting the Tett.Lett article on CC in acetone w/TEA.
[Edited on 10-2-2007 by Sauron]
Attachment: TCT_DMF.zip (589kB)
This file has been downloaded 1209 times
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Sauron
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@chemrox, the reference you are still lacking (after downloading above attachment) is Tett.Lett. 40 4395 (1999), author M.Faloomi et al.
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Organikum
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The industrial process for making alpha-chloropropionate starts from lactic acid + thionylchloride and the Ullmann says yields are a baffling 100%.
Chlorination of propionic acid is NOT trivial, old literature says that PCl3 is difficult and workup almost impossible.
I think that there is reason why industry starts with lactic acid and its not only the price......
Knowing that thionylchloride is hard to impossible to come by and PCl3 the same I remember having read something about chlorination with TCCA + a
small amount of PCl3 as "starter". A small amount of PCl3 can be produced without bigger problems (some P - can be even scraped from matchboxes - in
chloroform or DCM + dry chlorine gas should nicely produce PCl3, it makes SnCl4 and AlCl3 why not PCl3....). TCCA is easy and lactic acid should be
not so big a problem (getting it anhydrous might be a challenge though).
And where is now this benzaldehyde, oh! forgot! First we have to make some ester of this alpha-chloropropionate - well anhydrous alcohol and dry
HCl-gas should do the trick here or not? 
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garage chemist
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Red P in Chloroform + Chlorine I have done on a medium scale (10g red P in 100ml Chloroform, the Chloroform was previously dried over P2O5 and
distilled).
This exclusively produces phosphorus pentachloride. No PCl3 is present in the mix, even when red P is present in excess.
The PCl5 just refuses to react with more red P when in Chloroform (in the dry state it works, however).
http://www.versuchschemie.de/ptopic,124916,2d7537946855c29dc...
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Organikum
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PCl5? Even better. 
Das "von mir erfunden" ist aber ein wenig arg mutig oder nicht?
Danke & Nix für ungut!
/ORG
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Sauron
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I must have missed a post. We are discussing making pripionyl chloride not a-chloroprionic acid.
SOCl2 and PCl3 are reagents for acyl chlorides not alpha chlorination.
In Hell-Volhard-Zelinsky rxn you might use a catalytic amount of PCl3 or red P as halogen carrier but you could just as well use pyridine or sulfur or
SCl2 in same fashion and with similar results.
N-chlorosuccinide in CCl4 on the acid chloride is a specific a-chlorination reagent.
Likewise NBS to make the alpha-bromoacid chloride which is then converted back to the a-bromo acid. I use that one to make a-bromocaproic acid on my
way to norleucine. At least when I get tired of HVZ using up my Br2.
For acetic and proprionic acids, SOCl2 or PCl3 are problematic in workup for sure because of bp's too proximate (as Vogel advises) but again they'd be
making acid chloride not chloro acid. They work for C4 acids and higher. But I still say they have been made obsolete at least on lab scale by TCT,
TCT/DMF, benzoyl chloride, and oxalyl chloride. These work fine on acetic and propionic acids too.
[Edited on 15-2-2007 by Sauron]
[Edited on 15-2-2007 by Sauron]
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Organikum
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My bad. I apologize. But somehow this all sounded exactly like making alpha-chloropropionate, but I should have looked harder.
Pardon
/ORG
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chemrox
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sure is nasty stuff ... I tried a drying tube at the end of the 500mm west condenser .. wrong termination .. after being expelled from the lab (gotta
fix that hood fan) I ran a gas tube through a backflow trap and down the sink with the cooling water. Now i'v got a pot full of benzoic acid
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leu
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If the yield is sufficient, this approach would probably be the most facile for most Mssr Colson published this synthesis of propionyl chloride from propionic acid, acetonitrile and HCL gas in Comptes Rendus
121 1155-6 (1895) 
Attachment: colson.zip (30kB)
This file has been downloaded 1113 times
Chemistry is our Covalent Bond
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john_do
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How does one go about getting this text translated into english?
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Sauron
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@Leu, I downloaded that file and tried to open it with WinZip and got an error message saying it is not a valid zip file
WinRAR opened it but all that appeared was gibberish code.
Can you post this in unzipped form?
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S.C. Wack
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The problem is at your end again. Nothing wrong with it with winrar.
For something on-topic to say, an excerpt from JACS 44, 1746 (1922) that will not help the thread starter but the thread is here, so...
To 540 g. of propionic acid 245 g. of sulfur monochloride was added and chlorine
was passed through the mixture while it was stirred for 15 hours. The chlorination
proved to be incomplete at this point, since 150 g. of unchanged propionic acid was
recovered. There was also considerable sulfur monochloride, which was removed from
the propionyl chloride by treatment with hydrogen sulfide. The propionyl chloride obtained
amounted to 250 g.
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not_important
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On a WinDoze XP machine the OS unzipped the file fine, as did 7zip (free, multiplatform) under Windows and Linux.
There's been problems for various people with downloading some files recently. I do not think it is the original files, but some problem during
download.
Here is the unzipped form, reads just find with Irfanview + djv plugin. Compression saved about 1% it looks like.
And I just tried D/L on the attached, or more properly viewing in FireFox with the djv viewer plugin, and it went OK.
[Edited on 1-6-2007 by not_important]
Attachment: colson.djvu (30kB)
This file has been downloaded 860 times
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not_important
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With XP right-clicking on the file and selecting "Open with..." will let you select the built-in WinDoz zip function.
I've now been told that the zip file in questions was successfully processed by registered versions of Winzip 10.something and 11.1
If there are problems opening compressed attachments in the future, hopefully one of the options in the last few messages will solve the problems.
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Polverone
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I've removed the most off-topic junk from this thread. If people want to keep talking about software and file attachments, make a thread elsewhere.
PGP Key and corresponding e-mail address
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chemrox
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which is this TCT or CC or something else? It's called trichlorocynuric acid and it oxidizes sulfites to sulfoxides which can be useful
Attachment: RSR to RSOR by TCT.pdf (44kB)
This file has been downloaded 1506 times
"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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The paper title says trichloroISOcyanuric acid.
That is TCCA Not TCT/CC which are the same thing (TCT = CC)
We have several times posted the structures and proper nomenclature for both os these are are disinclined to do so again.
Suffice it to say that with TCCA the three chlorines are on nitrogen, it is a cyclic tri-chloramine commonly used as swimming pool chlorinator.
TCT (CC) is the acid chloride of cyanuric acid. The chlorines are on carbon, replacing -OH groups.
The empirical formulas are different, the molecular weights are different, the structural formulas are different. Why do people keep confusing these
two? Chemrox old friend, go sit in the corner facing the wall and wearing a pointy hat.
TCT contains no oxygen. It is C3N3Cl3.
TCCA is C3N3O3Cl3.
Their chemical behavior is very different as you might expect.
Sic gorgeamus a los subjectatus nunc.
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chemrox
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@Sauron -It sure does say "..iso.." that was careless. Thank you.
"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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No problem, even I have been wrong, once.
Sic gorgeamus a los subjectatus nunc.
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Klute
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Translation of Comptes Rendus, 121 1155-6 (1895)
ORGANIC CHEMISTRY- Synthesis of amide hydrochlorides and acid chlorides.
Note of Mr. Albert COLSON, presented by Mr. P. Schützenberger.
"On contact with hydrochloric acid, a lot of amides only fix one molecule of acid for two molecules of amide, and no general processes that only give
the stoechiometric combination of the two compounds are known. We present herein a process that simultanously give monohydrochlorides of amides and
acid chlorides, with great ease and high yields. After having mixed a nitrile with an acid, the mixture is saturated with dry gaseous hydrochloric
acid at 0°C. The reaction is the following:
RCN + R'COOH + 2HCl = RCONH2.HCl + R'COCl.
Examples: According to this equation, the following experiments are conducted:
1°- A stoechiometric mixture of acetonitrile CH3CN and acetic acid was saturated with dry hydrogen chloride at 0°C and left in a
sealed flask for a day. A large amount of acetamide monohydrochloride crystals CH3CONH2.HCl precipated; at the same time a corresponding amount of
acetyl chloride was formed.
2°- When replacing the acetic acid in this experiment by proprionic acid, the same hydrochloride was obtained aswell as an
equivalent amount of propionyl chloride.
3°- By saturating with dry hydrogen chloride some propionitrile CH3CH2CN dissolved in cooled acetic acid, a abondant amount of
propioamide monohydrochloride crystals CH3CH2CONH2.HCl were obtained the next day, aswell as some acetyl chloride.
4°- Formic acid, of which the chloride is unknown, decomposes itself much more readibly than its homologues: it gives carbon
monoxyde aswell as the hydrochloride of the nitrile employed.
The described process is thus a simple and practical way of obtaining acid chlorides without the use of dangerous phosphorus chloride, aswell as the
monohydrochloride of a amide.
Besides, the reaction on which this process is based on gives a new view on the esterification of alcohols by acides. We know that this operation is
usually done in presence of hydrogen chloride gas, and that the esterification of alcohols by acid chlorides is quantitative. The very efficient role
of hydrochloric acid is thus explained by the ease with which this gas converts organic acids into acid chlorides when a secondary compound removes
the water that is formed:
CH3COOH + HCl = CH3COCl + H2O
In the previous reactions, it's the nitrile that removes the water; during the esterification, it's another portion of the hydrochloric acid that
gives HCl +2H2O.
Furthermore, the amount of heat generated is comparable in the two cases.
Other process: The formation of acid chlorides is easier when the acid is replaced by it's anhydride. This was seen with acetic
anhydride:
(CH3CO)2O + 3HCl + CH3CN = 2CH3COCl + CH3CONH2.HCl
Thus, the explanation I gave about the formation of lactic diamides (Comptes Rendus, Dec 1895, p.825) must be modified. We
must consider the intermediate formation of an acid chloride that then reacts on the monoamide initially formed.
It's precisely when trying to control in simple experiments the explanation given in my last communication at the Academy that I discovered the
results of this present note. I thus suggest to generalize this method."
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Sauron
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Is this a suggested route to acetyl chloride?
Convenient if one has a cylinder of anhydrous HCl around.
Or a solution of HCl gas in AcOH. That is commercially available. At a rather high molarity if I recall.
Sic gorgeamus a los subjectatus nunc.
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Klute
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It's the translation of the french article Leu linked further up the thread.. Acetonitrile is not that expensive, and acetamide can be usefull for
many things, including as solvant. HCl can be easily generated, although at a relative large scale it produces alot of waste (dilute H2SO4, which
could be used to neutralize basic wastes). Could be worth a try, if someone was desperate for an acyl chloride. I guess benzoic acid could work too,
why not oxalic or phtalic acid?
HAs anyone ever stumbled on similar refs? I'd be willing to translate french ones.
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chemrox
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propionyl chloride experiment using TCT
At the suggestion of a member and one relying on memory I tried a synthesis of propionyl chloride using TCT by two different pocedures. I'm reporting
what I did here for the good of the order.
Pocedure I
1 mol, 184 g. TCT was combined with 10 moles, ~1000 ml, propionic acid in a flask fitted with a column, head and condenser. The receiver was set with
a drying tube and acid vapor exhaust line. The mixture was stirred and heated to reflux. It was held at reflux for a total of 10 hrs over two days.
About 20 ml of propionyl chloride and an unknown low boiling compound were collected (acetyl chloride? from where?)
The reaction mixture was cooled collected and the phases separated: unreacted TCT and propionic acid. The latter was distilled the following day
whereupon 800 ml acid were collected in a highly pure state.
Procedure II
1/2 mol TCT, 82 g was dissolved in the minimum, 600 ml, amount of technical acetone. 140 ml propionic acid was added and the mixture stirred in a
beaker. It was planned to add 138 ml of Et3N but the first few ml reacted vigorously and the addition was stopped while everything was transferred to
a reaction/distillation setup as above. The rest of the base was added over an hour. The reaction was mildly exothermic and produced a white
precipitate.
The mixtures will be re-evaluated in the morning. I think my brain slipped a gear while I was smoking on the porch and writing the numbers in my
notebook. If any remedial adjustments seem indicated they will be made in the morning prior to the first phase separation. The mixture was *supposed
to be* 1/2 mol: 1 mol: 1 mol. Obviously there's excess acid and base.
I plan to decant the liquid and filter the residue. The collected liquid will be flashed to get the acetone off and then distilled to collect the
propionyl cl. The white ppt is not Et3N-propionate. I checked by test tube exp. It should be DCT according to theory. I can check later by IR.
Post script :
I edited to explain a stoichiometric foible- I put basic info for each ingredient in my notebook and used the bp instead of the weight for the acid so
it's there in excess. Shouldn't make a difference but there it is..
[Edited on 30-1-2008 by chemrox]
"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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chemrox
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scale-up of anhydride prep failed
I wanted to make about 200 ml of prop anhydride and used the fused Na salt method. This was an example of scale-up not working. I ended up with a
lot of unreacted Na-prop, Br2 and some damp Na-prop in the 3L flask. The stirrer had to be manipulated by hand, barely moved the material around and
mixed it insufficiently. Eventually the stirrer blade became disconnected. Unpleasant experience. Br vapor in the eyes etc.. The one bright spot ws
my partner located a used eyewash station and we're picking it up next week and installing it asap. Will use the prop-Cl/Na-prop method next.
"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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tiger1
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The JACS 60 (6) 1325 1938 for propionyl cl with benzoyl chloride:propionic acid 3:2 is simple and it's very smooth. Simply charge both to RB flask
w/mag. stirring, heat to bp of 80 and you get a relatively pure fraction which if refractionated using a vigreux gives 80-90% or higher if you're
especially careful. Quick and clean. You can even recover the benzoic acid if desired with little effort. PCl5 also works well but is nasty to deal
with and is relatively expensive.
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