Sciencemadness Discussion Board

Oxalyl Chloride Challenge

JJay - 3-5-2018 at 09:50

After my proposed challenge, Total Synthesis of Lysergic Aldehyde, was rejected by the site moderators, I have decided to open up the Oxalyl Chloride Challenge!

The rules are a little bit different this time around:

1. You must synthesize oxalyl chloride without using any phosphorus compounds.
2. Your synthesis must be performed without using any chemicals that are available only from chemical suppliers. OTC materials and common industrial chemicals may be used, as can chemicals available from pottery suppliers, photo suppliers, cleaning suppliers, grocery stores, welding stores, garden stores, hardware stores, etc. Obviously, oxalic acid is an acceptable chemical to use in your synthesis, but anything as exotic as sodium borohydride is out. You can use chemicals successfully made by amateurs such as sodium, bromine, nitric acid, etc.
3. Your synthesis must not produce any phosgene as a byproduct.
4. If more than one submission is received, the submissions will be ranked according to how convenient they are and how easy it is to obtain the materials required, with the winning submission receiving the prize.
5. I reserve the right to close the competition before any submissions are received by producing oxalyl chloride in my own lab.
6. Once a documented synthesis of oxalyl chloride has been submitted, the contest will close within one one week if no further submission is made. If more than one submission is received, the contest will close exactly 7 days after the last submission.
7. Submissions will only be accepted if they document an actual synthesis of oxalyl chloride.

Possibly useful threads:
OTC Oxalyl Chloride Challenge
Modified Patent Route to Oxalyl Chloride

The prize will be some quartz labware. Oh and also bragging rights. Lots of them. All submissions should be attached to this thread. Questions can be asked here or via U2U.




Magpie - 3-5-2018 at 12:36

This is a worthy challenge. I will not submit my entry using homemade SOCl2.

Tsjerk - 3-5-2018 at 12:54

@Magpie; you would lose big time from my super OTC and easy method anyway ;)

I actually have an idea... I just have to get some anhydrous oxalic acid and something else. Should be easy to test on a gram scale whether it is worth pursuing.

I'm actually quite broke at the moment and in the foreseeable future... could anyone spare a couple grams of oxalic acid? I will post the photos here in case of failure, as I think the reaction is interesting anyway.

JJay - 3-5-2018 at 13:04

I have about 4500 grams of oxalic acid dihydrate and can easily send someone 10 grams or so if that would be helpful....

I've never made it, but the synthesis from sucrose looks pretty straightforward: https://www.youtube.com/watch?v=M5bAbvw6IQQ

Tsjerk - 3-5-2018 at 13:14

Ok, nevermind, I just found a 100 gram source for about 10 euros including shipping

clearly_not_atara - 3-5-2018 at 13:41

Maybe you can go via glyoxylic chloride, and chlorinate this to get the product? Glyoxylic acid is not the easiest target, but it is doable. You can form the anhydride by any of the standard procedures (S/Br2, S2Cl2, NO2, etc) and gas this with HCl, or you can try the unproven nitrile method: bubble HCl through a mixture of 2 parts benzonitrile to 1 part glyoxylic acid, giving glyoxylic acid (glyoxylyl?) chloride and N-benzoylbenzamidinium chloride.

Magpie - 3-5-2018 at 15:10

@Tsjerk: May we see the equation, please.

chemplayer... - 3-5-2018 at 18:10

One question, what's sort of 'proof of completion' is required, i.e. tests or quality criteria that need to be considered to say that oxalyl chloride has been produced?

JJay - 3-5-2018 at 18:30

One of the best ways to demonstrate that oxalyl chloride has been created would be to make TCPO and use it in a glowstick-type demonstration. Of course, other methods could be acceptable.... The synthesis should be repeatable and considered valid by a consensus (or at least an overwhelming majority) of amateur scientists.

theAngryLittleBunny - 4-5-2018 at 05:14

Oh wow, that sounds pretty cool, I think I have a way that would be pretty easy if it would work, and I don't see how it shouldn't work, so I'll give it a try!

JJay - 4-5-2018 at 18:45

I'm glad there is so much interest in this challenge. I'd appreciate it if a moderator would sticky this thread.

Tsjerk - 5-5-2018 at 00:49

Yeah! This morning my oxalic acid dihydrate came in. I did a really quick and definitely dirty dehydration by putting between 5 and 10 grams in the microwave. This works, is fast, but please don't do it in your mothers kitchen and stay up-wind. Probably some carbon monoxide was formed.

There were a lot of fumes, the oxalic acid partly burned, but it only took two minutes to get a couple of grams of nicely sublimated acid.

What I did was putting a glass bowl on top of another bowl with the two open sides onto each other. After 30 seconds the acid dissolved in its own water while starting to boil, after two minutes in the microwave there was no more oxalic in the bottom of the bottom bowl, except for a bit of completely carbonized acid, and a grayish ring where the acid started to condense (what is the correct term for this? From gas to solid?) Above this grey ring there were nice white crystals of presumable anhydrous acid. I scraped all white fluffy crystals off of the glass, the gray and black stuff were discarded.

The yield is probably below 50%, but I have enough anhydrous acid for the tests I want to do; hopefully this afternoon. Next time I will try if I can do it a little cleaner by halving the microwave power, do it in shorter burst while cooling the top bowl with some ice in between heating.

DSC_0017.jpg - 2MB
Bottom bowl, note that the bottom where the acid was is now completely clean (well, almost clean).

DSC_0015.jpg - 1.9MB
Two bowls like they were while microwaving

DSC_0016.jpg - 2.2MB
Top bowl after microwaving

DSC_0018.jpg - 2.3MB
Recovered fluffy white crystals

Texium - 5-5-2018 at 06:05

Wow, that's really nice. A lot cleaner than when I dehydrated some in a toaster oven once. More reason for me to see about getting a lab microwave at Goodwill.

Tsjerk - 5-5-2018 at 10:04

The field was a bit lower than I thought, I only scraped out 0.6 grams. Maybe a microwave with a hole in the top with a non-cooled condensor would be an idea.

I think I might have made something condensable chlorinated, fuming in the air, turning into a white solid upon exposure to moist air, today.

What I did was dissolving TCCA in concentrated sulfuric acid, cooled it to 5 degrees, added my 0.6 grams of anhydrous oxalic acid, then let it warm (nothing exothermic) to RT, warmed it to 60-80 degrees.

What I saw was bubbling and fumes from 60 degrees and up. I put a round bottom flask with ice water on top of the beaker
There was definitly chlorine gas coming off, but also some condensate on the round bottom.

The condensate(quite viscous) left a white precipitate after fuming in the air (I swapped the ice water for hot water).

My guesses are that the fume cannot be oxalic acid, as chlorine would oxidize that quickly, it can also not be water, as it was coming of concentrated sulfuric. The fumes were definitly HCl, as those are unmistakable.

Now the question is, what was condensing? It was coming of from 60 degrees and up (I overdid the heating big time), it was turning solid upon exposure to air. Could there be some cyanuric something evaporation? I heated the sulfuric to 90 degrees to get the TCCA to dissolve before adding the oxalic acid, no fumes there.

I will post pictures in a bit.



JJay - 5-5-2018 at 10:17

Be careful.

Tsjerk - 5-5-2018 at 10:35

https://www.google.nl/amp/s/www.researchgate.net/publication...



[Edited on 5-5-2018 by Tsjerk]

DSC_0026.JPG - 2.1MBDSC_0024.JPG - 2.1MB

theAngryLittleBunny - 5-5-2018 at 11:17

Quote: Originally posted by Tsjerk  
The field was a bit lower than I thought, I only scraped out 0.6 grams. Maybe a microwave with a hole in the top with a non-cooled condensor would be an idea.

I think I might have made something condensable chlorinated, fuming in the air, turning into a white solid upon exposure to moist air, today.

What I did was dissolving TCCA in concentrated sulfuric acid, cooled it to 5 degrees, added my 0.6 grams of anhydrous oxalic acid, then let it warm (nothing exothermic) to RT, warmed it to 60-80 degrees.

What I saw was bubbling and fumes from 60 degrees and up. I put a round bottom flask with ice water on top of the beaker
There was definitly chlorine gas coming off, but also some condensate on the round bottom.

The condensate(quite viscous) left a white precipitate after fuming in the air (I swapped the ice water for hot water).

My guesses are that the fume cannot be oxalic acid, as chlorine would oxidize that quickly, it can also not be water, as it was coming of concentrated sulfuric. The fumes were definitly HCl, as those are unmistakable.

Now the question is, what was condensing? It was coming of from 60 degrees and up (I overdid the heating big time), it was turning solid upon exposure to air. Could there be some cyanuric something evaporation? I heated the sulfuric to 90 degrees to get the TCCA to dissolve before adding the oxalic acid, no fumes there.

I will post pictures in a bit.




Be a bit more careful, what you did sounds quite dangerous tbh, because the chlorine could oxidize the oxalic acid, making stuff like phosgene. You don't need chlorine for that, because you don't wanna oxidize the oxalic acid, you need chloride which replaces the OH groups on the oxalic acid, like PCl5, SOCl2, stuff like that. And don't confuse TCCA with cyanuric chloride, they are not the same, not at all.

Tsjerk - 5-5-2018 at 11:43

I know, I know, it was not my intention to generate chlorine. I was hoping it would not evolve. I do think there is something here as I got a condensate while there was chlorine. It is not a question if chlorine will oxidize oxalic, it will for sure, definitely at 60 degrees.

Edit: Oxalyl cloride should be stable though in hot sulfuric and or chlorine


[Edited on 5-5-2018 by Tsjerk]

theAngryLittleBunny - 5-5-2018 at 13:10

Quote: Originally posted by Tsjerk  
I know, I know, it was not my intention to generate chlorine. I was hoping it would not evolve. I do think there is something here as I got a condensate while there was chlorine. It is not a question if chlorine will oxidize oxalic, it will for sure, definitely at 60 degrees.

Edit: Oxalyl cloride should be stable though in hot sulfuric and or chlorine


[Edited on 5-5-2018 by Tsjerk]


Still tho, the problem is that you used chlorine in the +1 oxidation state, but you need chlorine in the -1 oxidation state. For your reaction to work, it would have to generate trihydroxyisocyanuric acid, and I don't think that exists. I think treating carbon compounds where the carbon is in a higher oxidation state like +2, +3 with chlorine is always risky, because it could generate phosgene.

mackolol - 14-5-2018 at 10:01

Hi, today i tried synthesis of oxalyl chloride by chlorination of ethylene glycol. I have read an article about that and says that yield is nearly 100% if used solvent. They used o-dichlorobenzene. I have chosen tetrachloroethylene as it dissolves chlorine well and boils at 120C. So i attempted synthesis with my fresh obtained TCE. At the beginning everything was ok mixture turned green because of dissolved chlorine and heated. But as it was going it became cloudy and eventually it formed big crystal that blocked my magnetic stirrer. I found that it was hexachloroethane as it smelled the same and it was only option. So my question is how it was chlorinated to HCE if doug was attempting this with catalyst and under reflux and it almost didnt work and every patent says that it requires very strong light and other shit like that. I can also say that this was performed outside under daylight. Can anybody explain this and help what to do with this solvent?

Dr.Bob - 14-5-2018 at 11:14

Did you simply chlorinate the solvent TCE to add Cl across the double bond? Not sure how easy that is, but seems quite likely. That may be why they use o-dichlorobenzene as the solvent, as it is less likely to chlorinate in those conditions.

weilawei - 14-5-2018 at 12:43

Quote: Originally posted by theAngryLittleBunny  
Quote: Originally posted by Tsjerk  
I know, I know, it was not my intention to generate chlorine. I was hoping it would not evolve. I do think there is something here as I got a condensate while there was chlorine. It is not a question if chlorine will oxidize oxalic, it will for sure, definitely at 60 degrees.

Edit: Oxalyl cloride should be stable though in hot sulfuric and or chlorine


[Edited on 5-5-2018 by Tsjerk]


Still tho, the problem is that you used chlorine in the +1 oxidation state, but you need chlorine in the -1 oxidation state. For your reaction to work, it would have to generate trihydroxyisocyanuric acid, and I don't think that exists. I think treating carbon compounds where the carbon is in a higher oxidation state like +2, +3 with chlorine is always risky, because it could generate phosgene.


1,3,5-trihydroxyisocyanuric acid can be prepared, but it looks like it's not a simple procedure from quick searching. See here.

Edit: Aaaand here's the paper.

[Edited on 14-5-2018 by weilawei]

Attachment: THICA.pdf (261kB)
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clearly_not_atara - 4-8-2018 at 10:42

Quote:
I think I might have made something condensable chlorinated, fuming in the air, turning into a white solid upon exposure to moist air, today.

What I did was dissolving TCCA in concentrated sulfuric acid, cooled it to 5 degrees, added my 0.6 grams of anhydrous oxalic acid, then let it warm (nothing exothermic) to RT, warmed it to 60-80 degrees.

What I saw was bubbling and fumes from 60 degrees and up. I put a round bottom flask with ice water on top of the beaker
There was definitly chlorine gas coming off, but also some condensate on the round bottom.

The condensate(quite viscous) left a white precipitate after fuming in the air (I swapped the ice water for hot water).

My guesses are that the fume cannot be oxalic acid, as chlorine would oxidize that quickly, it can also not be water, as it was coming of concentrated sulfuric. The fumes were definitly HCl, as those are unmistakable.

Now the question is, what was condensing? It was coming of from 60 degrees and up (I overdid the heating big time), it was turning solid upon exposure to air. Could there be some cyanuric something evaporation? I heated the sulfuric to 90 degrees to get the TCCA to dissolve before adding the oxalic acid, no fumes there.


Two thoughts:

- TCCA is not TCT. TCT converts acids to acyl halides. TCCA is an oxidizer.

- Anyone attempting oxalyl chloride by deoxychlorination of oxalic acid needs a fume hood because dehydration of oxalic acid can quickly generate a lot of carbon monoxide. At the very least, you should have a carbon monoxide detector installed and good ventilation. There is no smell warning; you just get a headache, pass out, and die. CO will probably not be formed with TCCA and oxalic acid, though, thankfully.

JJay - 15-12-2018 at 01:14

I will be actively working to synthesize oxalyl chloride next week. I'll check back, and if someone has actually beaten me to the punch then I'll award the prize, but I have an advantage: under the rules, as the contest sponsor, I am permitted to use phosphorus compounds. So if you have a winning entry, now is the time to submit it.

morganbw - 15-12-2018 at 11:28

Somedays I drink and may post when I should be sleeping but here it is.
I did not read that you were allowed to cheat. Think my Harvard Grad!
Too smart to be so stupid.

Texium - 15-12-2018 at 11:55

Quote: Originally posted by JJay  
I will be actively working to synthesize oxalyl chloride next week. I'll check back, and if someone has actually beaten me to the punch then I'll award the prize, but I have an advantage: under the rules, as the contest sponsor, I am permitted to use phosphorus compounds. So if you have a winning entry, now is the time to submit it.
Yeah, I don't see anything about that in the OP. Lame.
But if you want to race, I could probably whip up some PCl5 next week...

JJay - 15-12-2018 at 13:47

Quote: Originally posted by Texium (zts16)  
Quote: Originally posted by JJay  
I will be actively working to synthesize oxalyl chloride next week. I'll check back, and if someone has actually beaten me to the punch then I'll award the prize, but I have an advantage: under the rules, as the contest sponsor, I am permitted to use phosphorus compounds. So if you have a winning entry, now is the time to submit it.
Yeah, I don't see anything about that in the OP. Lame.
But if you want to race, I could probably whip up some PCl5 next week...


Read the fine print.

I have a few things on my plate. You can probably do it faster, but the prize is for a non-phosphorus synth. Or if you want, you can take charge of the challenge, but then you have to award the prize. Up to you. I keep my word.

clearly_not_atara - 15-12-2018 at 14:20

Ok, I have one more stupid idea.

Suppose your starting materials are ethyl bromide, thiocyanate, DMSO, and acetyl chloride.
The first two give ethyl thiocyanate.
The second two give chloromethyl methyl sulfide:
https://pubs.acs.org/doi/abs/10.1021/ja01608a016?journalCode...

It should be possible to perform a Barbier-like reaction between these two to get ethyl thiomethylthioacetate. Chloromethyl methyl sulfide is likely to be a noxious chemical, but it should be less volatile than Me2S.

Oxidation with SeO2 should give oxalyl methyl-ethyl dithioester, which then might interact with SO2Cl2 to give oxalyl chloride.



[Edited on 15-12-2018 by clearly_not_atara]

Texium - 15-12-2018 at 18:25

Quote: Originally posted by JJay  
Quote: Originally posted by Texium (zts16)  
Quote: Originally posted by JJay  
I will be actively working to synthesize oxalyl chloride next week. I'll check back, and if someone has actually beaten me to the punch then I'll award the prize, but I have an advantage: under the rules, as the contest sponsor, I am permitted to use phosphorus compounds. So if you have a winning entry, now is the time to submit it.
Yeah, I don't see anything about that in the OP. Lame.
But if you want to race, I could probably whip up some PCl5 next week...


Read the fine print.

I have a few things on my plate. You can probably do it faster, but the prize is for a non-phosphorus synth. Or if you want, you can take charge of the challenge, but then you have to award the prize. Up to you. I keep my word.
I see no fine print to read.

I even searched for "phosphorus" on the first page of this thread and it was only mentioned twice- once in the OP where you said "You must synthesize oxalyl chloride without using any phosphorus compounds" and a second time in the quoted post.

JJay - 15-12-2018 at 18:43

Quote: Originally posted by JJay  

5. I reserve the right to close the competition before any submissions are received by producing oxalyl chloride in my own lab.




j_sum1 - 15-12-2018 at 18:48

Don't know what has you so upset Jjay. This seems like an overreaction.
I hope you reconsider. You will be missed.

andy1988 - 15-12-2018 at 22:12

I'd tried to reply to this thread earlier but it was closed, j_sum1 suggested I post it here.

I thoroughly enjoy your contributions JJay, and style of writing/debate e.g. [1][2].

Reminds me of reading through early 1900s scientific proceedings, authors have interesting argumentation and style (in this page, lavish praise for Dr. Cook) (somewhere in a different volume/book an author when challenged said if he was shown wrong, to treat his writing as detritus, reminded me of this forum).

To illuminate an example of what I believe JJay was referring to as blatant self-promotion, see my posting here and later that page Melgar here. I chuckled extensively but my intention was never to maintain such a script, but after writing it to try to pawn it off on someone else to maintain and run, such as streety. I really am a "lazy" programmer, I hate to do tasks outside of what I'm principally focused on and I pawn such tasks/projects off for others to do at work. I hardly have the focus/energy to do everything I do want to do.

My motivation in things is to learn, share knowledge, and teach; I don't care for praise or recognition. It brings me joy to bring others success! On this topic I am thankful for the efforts Melgar and streety had made (and countless others for their efforts on different subjects). Though I guess there are other things which bothered JJay in this matter, e.g. the suggestion of compensation for tasks, running contrary to the spirit of this forum (I'm sure this could be articulated better, but I have shopping to do before this night is through!).

[Edited on 16-12-2018 by andy1988]

JJay - 23-6-2020 at 07:50

This challenge is still on.

clearly_not_atara - 23-6-2020 at 12:54

2018 atara: lots of complicated ideas

2020 atara: fuck it just hit glyoxal with some chlorine and see what happens

(be careful!)

mackolol - 23-6-2020 at 13:09

Quote: Originally posted by clearly_not_atara  
2018 atara: lots of complicated ideas

2020 atara: fuck it just hit glyoxal with some chlorine and see what happens

(be careful!)

I have thought about that, but hoping that glyoxal will be formed in situ from ethylene glycol and chlorine. Unfortunately it rather didn't work.
I couldn't get glyoxal enywhere and synthesising it seems like something impossible.
Good luck in getting some.

JJay - 23-6-2020 at 14:59

Glyoxal can be prepared by the action of nitric acid on ethanol and purified by the bisulfite adduct, according to this 1850s paper: https://books.google.com/books?id=S1AwAAAAIAAJ&pg=PA39#v...

clearly_not_atara - 23-6-2020 at 17:29

Quote: Originally posted by mackolol  
hoping that glyoxal will be formed in situ from ethylene glycol and chlorine. Unfortunately it rather didn't work.

I don't think this can work because the intermediate glycolaldehyde immediately dimerizes

[Edited on 24-6-2020 by clearly_not_atara]

JJay - 24-6-2020 at 02:26

Quote: Originally posted by clearly_not_atara  
Quote: Originally posted by mackolol  
hoping that glyoxal will be formed in situ from ethylene glycol and chlorine. Unfortunately it rather didn't work.

I don't think this can work because the intermediate glycolaldehyde immediately dimerizes

[Edited on 24-6-2020 by clearly_not_atara]


The dimerization would be reversible, wouldn't it?


[Edited on 24-6-2020 by JJay]

mackolol - 24-6-2020 at 03:21

I have tried a few syntheses of glyoxal, one of it being Polish patent oxidation of ethylene glycol by blowing air into boiling mix of EG/copper acetate which was supposed to work as a catalyst. I don't know what was I expecting, but you can easily figure out that it didn't work for me.
I know how shitty aldehydes can be in terms of purification, and glyoxal, being the simplest dialdehyde is a nightmare to work with. I gave up on this.

And you know, I can buy glyoxal to be honest but besides it being pretty expensive, it is sold as a 40% solution in water... I don't know if isolating it from water solution and then dehydrating it can be done in reasonable yield and quantity.

[Edited on 24-6-2020 by mackolol]

JJay - 24-6-2020 at 08:33

I'd think that oxidation of ethylene glycol with PCC or chromium VI oxide peroxide etherate would work. I don't think the yields would be spectacular with chromium oxidizers.

TEMPO oxidation with something simple like bleach would be more environmentally friendly and perhaps higher-yielding.


Sigmatropic - 24-6-2020 at 12:27

Has anyone considered chlorinating ethylene carbonate and decomposing the tetrachloroethylene carbonate by some means? A cursory look gave me a a hit.

And I think ethylene carbonate can be made from urea and ethylene glycol quite easily, even without catalysts such as described here. I wouldn't be surprised if there is a thread on here about making dimethyl carbonate via a similar sequence.

Edit: ahh I see I broke rule 3 of OP, but why would you have that rule? It's not as if the product is any less nasty aside from being a liquid instead of a gas.

[Edited on 24-6-2020 by Sigmatropic]

clearly_not_atara - 24-6-2020 at 17:32

But "being a liquid instead of a gas" is the whole reason we use oxalyl chloride instead of phosgene in the first place!

If I were trying to make glyoxal from first principles, I'd try nitrosating acetaldehyde. That way you avoid a glycolaldehyde intermediate and produce the (stable?) glyoxal mono-oxime which can then be converted to the bisulfite adduct.

The reaction of ethanol with nitric acid seems to essentially accomplish the same thing, but with simpler starting materials and in situ hydrolysis of the mono-oxime. I wouldn't count out glyoxal until I'd given that method a shot.

JJay - 24-6-2020 at 20:24

I had an idea.

mfcd00018821-medium.png - 22kB

Trichloromethylbenzene is capable of chlorinating carboxylic acids. Would it be possible to chlorinate both acyl groups of oxalic acid simultaneously with a hexachlorinated xylene?





[Edited on 25-6-2020 by JJay]

Cou - 19-7-2020 at 00:23

Does oxalyl chloride usually require hazmat shipping? There are resellers that could drop ship it to you.

Tsjerk - 19-7-2020 at 01:05

That would among others violate rule 7 right :)

Sigmatropic - 19-7-2020 at 07:11

I just had another idea, what if you make ethylene oxalate from dimethyl/diethyl oxalate and ethylene glycol. Then chlorinate it to the tetrachloroethylene oxalate. That with either activated carbon or a tertiary amine catalyst should rearrange to two molecules of oxalyl chloride.
https://patents.google.com/patent/US2816287
https://patents.google.com/patent/US2816140A/en

I don't have a reason to make oxalyl chloride or a fume hood so I'm not about to start this :(.

Σldritch - 20-7-2020 at 00:25

As long as were speculating i would try doing it with Sulfur Tetrachloride with a lewis acid as a catalyst to stabilize the Sulfur Tetrachloride as Trichlorosulfonium. Ideally the reaction would follow the first equation:

2 Cl2 + (COOH)2 + S = (COCl)2 + SO2 + 2 HCl (catalytic)
2+x Cl2 + (COOH)2 + S + 2 M = (COCl)2 + SO2 + 2 MClx•HCl (non-catalytic)

I tried making making Trichlorosulfonium Tetrachloroferrate (SCl3FeCl4) once but it failed because the iron wire did not react fast enough (use sulfides, would probably even work with aluminium). If i had the time i would try again with Stannic Sulfide to make Trichlorosulfonium Hexachlorostannate ((SCl3)2SnCl6) which is known to exist and requires less chlorine which is better if the lewis acid becomes inactive by the formation of a hydrogen chloride complex (in tin's case hexachlorostannic acid). Another problem which may be encountered is the oxidation of oxalic acid by chlorine. It could be avoided by first forming the Trichlorosulfonium and and then adding oxalic acid though it would not be as convenient. (May be necessary anyway to regenerate lewis acid by decomposition of any Hydrogen Chloride complex) I imagine it is a good idea to select a metal that does not form a stable oxalate either, a condition i believe tin (IV) fulfills. The last issue i can forsee is the different temperatures needed for the chlorination too dichlorosulfur (high) and trichlorosulfonium (low?) which may prevent the continuous process either by volatilization of the metal chloride or the instability on trichlorosulfonium, both issues are obvious how to solve. Anyway if it works workup would be very easy, just distill off the oxalyl chloride from the metal chloride - a useful side product. I believe this method is the most likely to work, i would love to see someone give it another try.

http://sulphur.atomistry.com/sulphur_tetrachloride.html


[Edited on 20-7-2020 by Σldritch]

clearly_not_atara - 10-9-2020 at 20:39

It turns out to be possible to make acetylenediol diisopropyl ether from glyoxal and isopropanol:

https://www.sciencedirect.com/science/article/abs/pii/S00404...

The addition of two equivalents of chlorine gives 1,2-diisopropoxy-1,1,2,2-tetrachloroethane, which, on pyrolysis, ought to give isopropyl chloride, 2-isopropoxydichloroacetyl chloride, and oxalyl chloride, by analogy to the decomposition of the diethoxy compound described by Baganz et al in the attached.

Thus: a phosphorous-free route entirely from published procedures.

EDIT: Ok, so Bou et al are using PCl5 to convert the glyoxal diacetals into a dichloroether. But this transformation can be achieved instead with ZnCl2/AcCl as described by Berliner and Belecki. Also, the prep of the dichlorodimethoxyethane intermediate is apparently a unique reaction.

Plausible, but extremely laborious. There may be other ways to achieve the requisite ethylene-1,2-diether, such as an Ullmann-type vinyl halide-alkoxide coupling.

[Edited on 12-9-2020 by clearly_not_atara]

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sffap - 17-2-2021 at 17:30

bump

any progress on this front? I'm running out of popcorn.

MaeBorowski - 13-3-2021 at 16:55

everyone is lazy

IMHO, the most appropriate way is the decomposition of chlorination products of ethylene oxalate or ethylene carbonate.

Ethylene oxalate [poly(ethylene oxalate)?] can be easily prepared by boiling equivalent amounts of ethylene glycol and oxalic acid (you can, even need, dihydrate) in carbon tetrachloride with a reverse Dean-Stark trap. I plan to do this synthesis sometime. :)

Ethylene carbonate is synthesized in various ways, but the simplest and most accessible to the garage chemist is the interaction of ethylene glycol with urea at low pressure and high temperature (doi:10.1039/b304182d). I find this route more advantageous, since urea is cheaper than oxalic acid, ethylene carbonate is easy to purify by distillation even at atmospheric pressure, and yields are higher than with ethylene oxalate.

Triflic Acid - 25-3-2021 at 06:30

And, how are you going to deal with that nice chlorinated decomposition product COCl2, commonly called phosgene? One member is believed to have died from phosgene poisonings a few years back. Do you even have a citation to prove what you said? I seriously doubt that this will give oxalyl chloride in anything above dismal yields. You should also give more information regarding what you mean by chlorinated products, just saying that they are derived from ethylene oxalate does not tell us anything.

Sigmatropic - 25-3-2021 at 11:06

Quote: Originally posted by Sigmatropic  
I just had another idea, what if you make ethylene oxalate from dimethyl/diethyl oxalate and ethylene glycol. Then chlorinate it to the tetrachloroethylene oxalate. That with either activated carbon or a tertiary amine catalyst should rearrange to two molecules of oxalyl chloride.
https://patents.google.com/patent/US2816287
https://patents.google.com/patent/US2816140A/en

I don't have a reason to make oxalyl chloride or a fume hood so I'm not about to start this :(.


Triflic Acid, I found some patents while ago, right before getting flamed by Eldritch. Patents are arguably not te best source of information but there is atleast some literature to support this dubious proposition.

mackolol - 25-3-2021 at 11:07

Quote: Originally posted by Triflic Acid  
And, how are you going to deal with that nice chlorinated decomposition product COCl2, commonly called phosgene? One member is believed to have died from phosgene poisonings a few years back.

Go outside and wear a gasmask. Am I missing something?

Triflic Acid - 25-3-2021 at 12:20

Oh, when he said decomposition, I immediately thought that he was doing something around pyrolysis. A hot bubbling phosgene gyser is not the best thing to deal with. If he's doing it with a tertairy amine its safer.

njl - 25-3-2021 at 13:25

@mack indeed you are missing something, namely the fact that a supplied air respirator is necessary according to the CDC (but that's just the man trying to keep us amateur chemists down). So a surplus Israeli gas mask that has a 40 year old filter might not cut it. And the rules say no phosgene. And no source is provided.

Right now I can't imagine a decomposition of "chlorinated ethylene carbonate" that doesn't involve carbonate itself, which would form water in its own decomposition thus destroying some product. But I could be totally off.

mackolol - 25-3-2021 at 13:48

Probably if you work with it all the time under the fan you would need the supplied air respirator.
But to be honest, when you're outside and in your gasmask, you could even hold the breath when you get close to it to make sure you don't expose yourself too much.
Of course any accident would be really dangerous, but it's probably not that bad

MaeBorowski - 27-3-2021 at 18:09

Quote: Originally posted by Triflic Acid  
And, how are you going to deal with that nice chlorinated decomposition product COCl2, commonly called phosgene?

There is an option to dump it on the absorption column, but it would be better to use it to produce new ethylene carbonate or put it in some solvent like toluene or other useful purposes for the chemist. This is quite dangerous, however, I have some experience with highly toxic gases (in my case carbon monoxide, but phosgene is much, much angrier) outside the fume hood. Don't do this yourself.
Quote: Originally posted by Triflic Acid  
saying that they are derived from ethylene oxalate does not tell us anything.

It can be concluded that the product of the exhaustive chlorination of ethylene oxalate will be tetrachloroethylene oxalate :)
Quote: Originally posted by njl  
And the rules say no phosgene.

I apologize for not mentioning the release of phosgene in the ethylene carbonate method. I tried to find a rational method through one's lens and completely forgot about the rules. Thank you for pointing out my mistake.
Quote: Originally posted by njl  
And no source is provided.

To be honest, I have no sources for the direct reaction of oxalic acid with ethylene glycol. In my opinion, there are no theoretical obstacles in this synthesis: water is distilled with carbon tetrachloride, which shifts the equilibrium, and oxalic acid is strong enough to carry out the reaction without a catalyst. It should be remembered that the difference between theory and practice is much greater in practice than in theory :)

clearly_not_atara - 28-3-2021 at 07:45

Quote:
It can be concluded that the product of the exhaustive chlorination of ethylene oxalate will be tetrachloroethylene oxalate :)

This is a pretty stark example of textbook chemistry with no consideration of the real world. Free-radical chlorinations like you refer to run slowly at low concentration and low temperature with a strong UV light. Running that can be pretty annoying.

Could it work? Yeah. Is it practical? Probably not. Could it fail? Yes: HCl byproduct might cleave the ester before chlorination completes. Is it basically the same thing as free-radical chlorination of glyoxal, which was suggested almost immediately? Yes. Does it satisfy the conditions of the bet? No: phosgene production is pretty likely when Cl* radicals interact with oxalate...

EDIT: third idea: rxn of 1,2-dibromoethane with two equivalents of phenol under Ullmann condensation conditions to 1,2-diphenoxyethylene, then Br2, DBU, NaNH2, 2xCl2. Same as the previous with a different way of forming the vinylene-1,2-diether.

[Edited on 28-3-2021 by clearly_not_atara]

MaeBorowski - 29-3-2021 at 07:32

Quote: Originally posted by clearly_not_atara  
This is a pretty stark example of textbook chemistry with no consideration of the real world.

You're goddamn right. But only partially: the product of chlorination isn't a tetrachloroethylene oxalate. In reality, chlorination requires 6.76 mol of chlorine versus the theoretical 4 (carbonate 4.93 mol vs the same 4), which indicates that there are changes in the oxalic acid residue. It is strange that in the production of oxalyl chloride, phosgene is released from tetrachloroethylene bis-chloroformate, which, in theory, should be obtained by breaking the carbon-carbon bond in the oxalic acid residue, but phosgene isn't obtained from the "tetrachloroethylene oxalate" itself, according to the data. Now I am even more interested in this idea.
Quote: Originally posted by clearly_not_atara  
low temperature with a strong UV light

The synthesis took place under a reflux. UV, I think, can be replaced by direct sunlight. This was used in some older manuals.
Quote: Originally posted by clearly_not_atara  
HCl byproduct might cleave the ester before chlorination complete

By hydrolysis? :P Most esters are perfectly resistant to hydrogen chloride.
Quote: Originally posted by clearly_not_atara  
free-radical chlorination of glyoxal

Something in me says that we will get hydrogen chloride and carbon monoxide instead of the coveted oxalyl chloride.
Quote: Originally posted by clearly_not_atara  
phosgene

In the process of decomposition — possibly, in the process of chlorination — excluded. If there is phosgene, it will be in such concentrations that hydrogen chloride is a bigger problem.
Quote: Originally posted by clearly_not_atara  
third idea: rxn of 1,2-dibromoethane with two equivalents of phenol under Ullmann condensation conditions to 1,2-diphenoxyethylene, then Br2, DBU, NaNH2, 2xCl2. Same as the previous with a different way of forming the vinylene-1,2-diether.

In Russian, to describe such syntheses, there is a stable expression "to hammer nails with a microscope". This is a possible way, I agree, but everyone who can repeat it has a) a fume hood b) several kgs of oxalyl chloride :)

[Edited on 29-3-2021 by MaeBorowski]

clearly_not_atara - 29-3-2021 at 14:35

Okay, your chemistry isn't wrong, you just don't seem to understand what JJay wanted. As to why, I don't know, he left the forum in a huff some months ago. Phosgene simply isn't allowed. It might be contained by someone sufficiently dedicated, but its generation is strongly discouraged here due to the sneaky lethality and common use of improvised safety equipment, which are a bad combination.

That kinetically stable chloroformates appear, rather than phosgene being released, does make sense to me. That is an interesting process.

When I said "free radical chlorination of glyoxal", I undersold the problems with this route, I agree. Homolytic cleavage of the radical intermediate is an issue I didn't consider. I'm not convinced it will happen, but polymerization is another problem.

How about free-radical chlorination of phenoxyacetyl chloride? Now that's three steps:

phenol + chloroacetic acid >> phenoxyacetic acid + SOCl2 >> phenoxyacetyl chloride etc.

EDIT: free-radical chlorination is not required, ordinary enol chlorination will do

[Edited on 29-3-2021 by clearly_not_atara]

mr_bovinejony - 29-3-2021 at 19:07

Is there a way from oxalyl bromide to oxalyl chloride? Or is it only possible from chloride to bromide? Bromine is much easier to handle than chlorine I think

Triflic Acid - 30-3-2021 at 05:48

I just saw something on prepchem: https://prepchem.com/oxalyl-chloride/. It is the ethyl carbonate synth, but sure enough, it makes phosgene. Also, I think that it is only a one way thing going from bromide to chlorine, https://www.prepchem.com/synthesis-oxalyl-bromide/.

MaeBorowski - 2-4-2021 at 17:53

Quote: Originally posted by mr_bovinejony  
Bromine is much easier to handle than chlorine I think

I've worked with both chlorine and bromine. The second one is much more smelly and corrosive, and, moreover, not cheap.
The problem with bromine is the need to dry it. This requires additional synthesis steps, whereas to produce dry chlorine, you only need a chlorine generator and a flask of concentrated sulfuric acid. Due to the gaseous state, you can not worry about contamination and assemble the glasswares on paraffinized rubber plugs.

Opylation - 21-5-2021 at 17:47

Has someone already mentioned the benzyl alcohol to benzoyl chloride reaction? Then Benzoyl chloride + oxalic acid -> Benzoic acid + oxalyl chloride reaction. This seems like the most OTC reaction to me. The oxalyl chloride boils out pushing the equilibrium to the right-hand side

[Edited on 22-5-2021 by Opylation]

clearly_not_atara - 22-5-2021 at 08:26

BzCl + H2C2O4 >> BzOH + CO2 + CO + HCl

Next!

S.C. Wack - 22-5-2021 at 10:43

Some benzoic anhydride seems likely, as it's a general method for anhydrides. Same for benzotrichloride...I wonder what the yield of benzaldehyde from benzal chloride and oxalic acid is.

Opylation - 22-5-2021 at 19:57

Quote: Originally posted by clearly_not_atara  
BzCl + H2C2O4 >> BzOH + CO2 + CO + HCl

Next!


Ouch! hahah oh well, I guess using BzCl for acyl chloride preparation can't be used for everything. There is a neat Thionyl Chloride preparation from, I think, phthalic anhydride and SO2. Let me see if I can find it

EDIT: Curiously, would using alkyl oxalate esters stabilize the reaction?

EDIT2: Found it! I also had a screen grab of a post from this forum, but didn't include the poster. I apologize in advance for not giving credit to that person but they pointed me to this paper. It actually uses phthalyl chloride which reacts to form phthalic anhydride in a reversible reaction

EDIT3: I also found another paper regarding the use of tetrachloroethylene carbonate as a precursor, which can be prepared from ethylene carbonate and chlorine. The issue with this method is that it also produces phosgene, which isn't the nicest of chemicals to work with. Since it's produced in-situ however, maybe using a double wash bottle; the first you're preferred absolute carboxylic acid (double product fun!), and the second being either sodium hydroxide solution or ammonium hydroxide solution to scrub the remaining phosgene. I'm sure if you use concentrated sulfuric acid as grease and perform this entirely outside with the proper precautions it could be done responsibly.

EDIT4: I'm sorry, I guess I'm beating the dead horse on that last mention. That method has been mentioned plenty in this thread

Attachment: kyrides1937.pdf (318kB)
This file has been downloaded 94 times

Attachment: Process for the Production of Oxalyl Chloride (US Patent 2816140) (1).pdf (293kB)
This file has been downloaded 87 times

[Edited on 23-5-2021 by Opylation]

Opylation - 3-6-2021 at 18:48

I was just thinking back to the ethylene carbonate -> chlorination -> oxalyl chloride + phosgene reaction and got to thinking would the transesterification of dialkyl oxalate to ethylene oxalate work? This forms 1,4-dioxane-2,3-dione. Theres a similar compound, Dioxalin, that is formed with oxalic acid and glycerol but the branching carbon group may stabilize it. I couldn't find any information on the formation of the 2,3-dione of dioxane which leads me to believe it's too unstable. But, if it were possible to form this compound, than the tetrachlorination followed by heating would liberate 2 moles of oxalyl chloride?

Jenks - 4-6-2021 at 09:29

That's a really brilliant idea. Happily, 1,4-dioxane-2,3-dione is known, CAS# 3524-70-7. The link shows that it is normally made from ethylene glycol and ... oxalyl chloride.

Opylation - 4-6-2021 at 09:49

I found a paper on cyclic oxalate ester formation and properties. It looks like ethylene oxalate has a high propensity to hydrolyze and polymerize/demolymerize. However, the paper does mention a preparation, so if used immediately it might be possible to prepare the tetrachloro derivative.

P.S. it uses transesterification for the prep :)

Attachment: carothers1930.pdf (2.5MB)
This file has been downloaded 78 times


[Edited on 4-6-2021 by Opylation]

Opylation - 8-6-2021 at 01:12

Just would like to provide an update that I have found a patent on the preparation of tetrachloroethylene oxalate via the transesterification of dialkyl oxalate and ethylene glycol followed by UV radical chlorination in carbon tetrachloride. Seems like a decent procedure to bump/update the thread for anyone who is curious :)

Attachment: Tetrachloroethylene oxalate.pdf (435kB)
This file has been downloaded 76 times

[Edited on 8-6-2021 by Opylation]

BauArf56 - 8-6-2021 at 01:39

if this reaction is reversible, first oxalic acid could be treated with bromine (which can be made from pool sanitizer sodium bromide), getting oxalyl bromide. Then it could be treated with hydrogen chloride gas, yielding oxalyl chloride.





[Edited on 8-6-2021 by BauArf56]

cocm.png - 35kB

Opylation - 8-6-2021 at 01:58

Liquid bromine and Oxalic acid react to form hypobromic acid, carbon monoxide and carbon dioxide. Hypobromic acid reacts with oxalic acid to form hydrogen bromide, water, and CO2

BauArf56 - 8-6-2021 at 02:32

forgot that bromine is an oxidiser! How about using hydrogen bromide instead of bromine? HBr could be made in situ with sulfuric acid and sodium bromide

clearly_not_atara - 8-6-2021 at 09:00

This thread doesn't need more random guesses from people who didn't bother to study the problem at all. HBr will not brominate any carboxylic acid, much less oxalic.

Opylation - 8-6-2021 at 16:29

I would like to post one more paper, a parent actually, that describes the preparation on oxalyl chloride via tetrachloroethylene oxalate. I feel like this could be the holy grail in oxalyl chloride preparation from OTC resources. Unless someone else has a better method.

Attachment: Tetchloret oxalate to Oxalyl Chloride.pdf (442kB)
This file has been downloaded 115 times


clearly_not_atara - 9-6-2021 at 04:50

That patent was already posted here:
https://www.sciencemadness.org/whisper/viewthread.php?tid=82...

Did you read the thread? Please, read the threads. We don't need more repetition, either.

njl - 9-6-2021 at 08:10

What if we tried chlorinating glyoxal???

karlos³ - 9-6-2021 at 10:45

Quote: Originally posted by njl  
What if we tried chlorinating glyoxal???

Tried to search for that term in this thread?
Because atara said this:
Quote:

Did you read the thread? Please, read the threads. We don't need more repetition, either.

I would second that, but I rather suggest to, maybe, just read the thread instead? :P

clearly_not_atara - 9-6-2021 at 11:43

njl was making a joke, I think :D

karlos³ - 9-6-2021 at 11:47

Damn... I guess I am "angloautistic" then, because I failed to grasp that, and often do so with obvious jokes when they're in english :o

Opylation - 9-6-2021 at 17:44

Off topic… removed for irrelevance

[Edited on 10-6-2021 by Opylation]

Praxichys - 7-7-2021 at 07:42

My lab is being moved but there is a lot of promise in (trihalomethyl)arenes like benzotrichloride and 1,3 and 1,4 bis(trichloromethyl)benzene. I did some research on this years ago during my SOCl2 and acetic anyhdride preps.

Each is easily produced through exhaustive uv photochlorination of toluene or xylene and does not have the side products involved with radical chlorination of carbonates or esters like methyl formate. A germicidal lamp, quartz flask, and chlorine generator make this pretty trivial albeit tedious.

These react with carboxylic acids (US 1,921,767 etc) to form acid chlorides and benzoyl chloride.

Where M is the arene:

RCOOH + M(MeCl3) --> RCOCl + M(COCl) + HCl

This happens at 80-140°C with a variety of available catalysts and the oxalyl chloride should continuously distill out.

I saw JJay had this as cursory suggestion further up but nobody followed up on it. I am not able to use my lab right now but I'd venture to guess this works as long as you're okay with 6+ moles of chlorine for every 1 of oxalyl chloride and a side product of 2 moles of benzoyl chloride. The waste economy goes up to 1:2 if you can hexachlorinate xylenes but the chlorine usage is the same.

S.C. Wack - 7-7-2021 at 19:02

My guess is that it would not be unwise to use an inexpensive, disposable reactor when heating anhydrous oxalic acid with Ar(CCl3)x, (when x is >1) and to expect 0.0000% yield of oxalyl chloride.

[Edited on 8-7-2021 by S.C. Wack]

Praxichys - 12-7-2021 at 06:43

Quote: Originally posted by S.C. Wack  
My guess is that it would not be unwise to use an inexpensive, disposable reactor when heating anhydrous oxalic acid with Ar(CCl3)x, (when x is >1) and to expect 0.0000% yield of oxalyl chloride.


Any particular reason for that assessment?

AcidChloride.jpg - 70kB

Jenks - 12-7-2021 at 07:20

Am I right in thinking that the difficulty with making oxalyl chloride is that when one end of oxalic acid is made into the acid chloride, the other half decarboxylates?

S.C. Wack - 12-7-2021 at 14:57

Quote: Originally posted by Praxichys  
Any particular reason for that assessment?


Quote: Originally posted by S.C. Wack  
Some benzoic anhydride seems likely, as it's a general method for anhydrides. Same for benzotrichloride


C6H5CCl3 + C2O4H2 = C6H5COCl + 2HCl + CO2 + CO
2C6H5COCl + C2O4H2 = (C6H5CO)2O + 2HCl + CO2 + CO
dates to no later than 1884.

Those able to remember 17 years of history may recall my referring to Roscoe and Schorlemmer...what do they say about oxalyl chloride asks no one..."From these decompositions it is clear that neither the anhydride nor the chloride of oxalyl can be prepared by the reactions which are employed for the preparation of the corresponding derivatives of other organic acids." This includes your patent.

BTW acetyl chloride and benzoyl chloride from benzotrichloride was patented in Germany 50 years earlier than that. They too left oxalyl chloride for others, but did also claim benzyl acetate, acetyl chloride, and ethyl chloride from ethyl acetate. With benzal chloride: ethyl chloride and benzaldehyde with ethanol, or benzaldehyde, acetyl chloride, and ethyl chloride with ethyl acetate, or benzaldehyde, acetyl chloride, and HCl with acetic acid. They did claim formic or anhydrous oxalic acid plus benzotrichloride and zinc acetate/chloride...to make benzoic acid. That was figured out by 1879.

[Edited on 13-7-2021 by S.C. Wack]

RustyShackleford - 13-7-2021 at 05:11

Quote: Originally posted by Praxichys  
My lab is being moved but there is a lot of promise in (trihalomethyl)arenes like benzotrichloride and 1,3 and 1,4 bis(trichloromethyl)benzene. I did some research on this years ago during my SOCl2 and acetic anyhdride preps.

Each is easily produced through exhaustive uv photochlorination of toluene or xylene and does not have the side products involved with radical chlorination of carbonates or esters like methyl formate. A germicidal lamp, quartz flask, and chlorine generator make this pretty trivial albeit tedious.

These react with carboxylic acids (US 1,921,767 etc) to form acid chlorides and benzoyl chloride.

Where M is the arene:

RCOOH + M(MeCl3) --> RCOCl + M(COCl) + HCl

This happens at 80-140°C with a variety of available catalysts and the oxalyl chloride should continuously distill out.

I saw JJay had this as cursory suggestion further up but nobody followed up on it. I am not able to use my lab right now but I'd venture to guess this works as long as you're okay with 6+ moles of chlorine for every 1 of oxalyl chloride and a side product of 2 moles of benzoyl chloride. The waste economy goes up to 1:2 if you can hexachlorinate xylenes but the chlorine usage is the same.


This apparently does not work with oxalic acid. Relevant sentence from patent US1963749A :
When a side chain polychlorinated product, such as benzotrichloride, is caused to react with dicarboxylic acid such as oxalic acid, benzoyl chloride and benzoic acid anhydride are formed without the formation of dicarboxylic acid ch10 rides such as oxalyl chloride.

Praxichys - 13-7-2021 at 07:09

Well, beans. Back to the drawing board.

Triflic Acid - 13-7-2021 at 15:01

Wait. Maybe this is too good to be true, but doesn't Atrazine, the pesticide, contain one of the chlorines of the cyanuric chloride?

https://en.wikipedia.org/wiki/Atrazine

Its also easily buyable:
https://www.ebay.com/itm/324527296326?epid=2256058930&ha...
https://www.ebay.com/itm/373597029173?epid=2254546174&ha...

MaeBorowski - 5-8-2021 at 14:40

And how will this help in the synthesis of oxalyl chloride?

Triflic Acid - 5-8-2021 at 15:44

cyanuric chloride reacts with oxalyl acid to form oxalyl chloride

clearly_not_atara - 5-8-2021 at 17:30

Unfortunately atrazine is nowhere near as reactive as cyanuric chloride due to the electron density donated to the ring by the amino groups. Compare trichlorobenzene with 3,5-diaminochlorobenzene, for example.

JJay - 6-8-2021 at 00:30

Quote: Originally posted by Triflic Acid  
cyanuric chloride reacts with oxalyl acid to form oxalyl chloride


Does it?

https://chemistry.mdma.ch/hiveboard/rhodium/cyanuric.chlorid...

The product here is oxalyl dianilide. If oxalyl chloride is an intermediate, it should be possible to isolate it. I would question whether oxalyl chloride is ever actually formed or if the reaction proceeds through monochlorinated oxalic acid derivatives.

Triflic Acid - 6-8-2021 at 07:07

So the oxalyl chloride produced reacts with the free amine on the atrazine. Maybe making the dihydrochloride salt would work, ammonium salts are generally much less reactive.

JJay - 20-8-2021 at 12:04

I haven't had this flask out in a while.

IMG_20210820_100917649.png - 154kB

Triflic Acid - 23-8-2021 at 16:19

So?

garphield - 13-9-2021 at 12:09

https://pubs.acs.org/doi/pdf/10.1021/acs.joc.5b01707

If this works for diacetyl, you'd be able to get oxalyl chloride from just diacetyl + sulfur + chlorine. It may not work, but it could be worth trying.