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National Hazard
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| Quote: | Originally posted by Jor
To many of us, PCl5 is not available. |
Come on where is that amateur spirit? Simply just make your own phosphorus pentachloride. 
| Quote: | | If one has PCl5, there's no need for TCT AFAIK |
That depends on what you are trying to do, for a chlorinating agent if you have PCl5 then you likley won't need it, as a reactant in other reactions
you will.
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Klute
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In some insatnce you can't use PCl5 for chlorinations, if you product has the same bp as POCl3 for example. With TCT, all you need to do if filter the
cynauric acid!
I really think the method Sauron advocates ei chlorinating CNCl through it's in situ formation by chlorination of alkyl/alkali thiocyanates is really
a good idea, and the mosyt practical way to do so. If you are carefull enough and think your way through, generating large amouts of chlorine gas
safely isn't very hard, dangerous or expensive, and the reaction yields very usefull/hard to get products.
Obviosuly, if you have a good source of red phosphorus (read not match boxes  ),
you can make PCl5 in a easier way IMHO.
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
-Alice Parr
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Sauron
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As the thread author, I'd like to point out that the prep of TCT by the trimerization of cyanogen chloride, as described above, is a very hazardous
procedure. There is a far safer process for preparing TCT, which is the chlorination using elemental chlorine, of methyl thiocyanate.
I have described this chlorination elsewhere, q.v. the product initially is a mixture from which TCT precipitates out in good yield. Chlorination is
continuied till no more TCT seperates. The supernatant liquid mixture is a mixture of CCl3SCl, which is toxic and highly irritating, and CSCl2, also
toxic and irritating. But these liquids are a lot less toxic than the gaseous HCN and ClCN involved in the other procedure.
Exhaustive chlorination of the mixture leads to CCl2 and sulfur chlorides.
From 100 g MeSCN aboit 65-70 g TCT is obtained.
The stoichiometry is given in the other thread, along with the original literature.
For those in the EU where TCT is often classes too toxic to sell to individuals, this is a good alternative. Methyl thiocyanate can be prepared from
KSCN and iodomethane or dimethyl sulfate, or by a somewhat more circuitous route starting with CS2.
Chlorination of cyanuric acid with PCl5 is terribly reagent intensive. Look at the stoichiometry and the molecular weights involved and you will see
what I mean. This is also the case with the preparation of oxalyl chloride from PCl5. This simply not a very practical method, unless you have no
other choice. This is without consideration of the logostical difficulties. PCl5 IS hard to obtain. Red P to make it, IS also hard to obtain in most
places. PCl5 could be made from PCl3 but that is also hard to purchase.
[Edited on 3-6-2008 by Sauron]
Sic gorgeamus a los subjectatus nunc.
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trilobite
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Here's a patent on production of cyanogen chloride from sodium cyanide and chlorine in organic solvent in the presence of a small amount of ethanol.
They say that adding more than the required amount of chlorine should be avoided. Who knows, maybe it's to avoid tri/polymerization.
Process of making cyanogen chlorides
US1779984
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Sauron
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Making cyanogen chloride is not difficult. It's surviving the making of cyanogen chloride that is the trick.
The point of my last post was a better way of making cyanuric (NOT cyanogen) chloride (TCT) WITHOUT having to make cyanogen chloride even in situ.
No one who does not have an industrial grade scrubber and hood AND a SCBA should attempt making cyanogen chloride. To do so in a residential
environment is to put your family at riak and possibly your neighbors as well. It's irresponsible.
The alternative I presented involves some toxic irritants but they are liquids not gases and therefore a lot easier to control. Once the pptd TCT is
removed, these are to be exhaustively chlorinated to CCl4. There's no other product except chlorides of sulfur. There is no explosion hazard as there
is with cyanogen chloride. My advice is leave that route to industry.
Sic gorgeamus a los subjectatus nunc.
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trilobite
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Understood. My purpose, on the other hand, was to contribute to the discussion by finding a literature reference for making cyanogen chloride in
nonaqueous conditions from NaCN without the need to handle HCN. This must be the right thread also for this piece of information considering all the
material posted here on routes which employ HCN. Of course, there is a lot more to succesfully making TCT by one pot chlorination of NaCN and
trimerization without killing oneself or others.
I assume people reading this thread have already understood they should not attempt this stuff without necessary precautions. I myself am only
interested in this stuff from the theoretical point of view because neither route is really my cup of tea.
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Sauron
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At the time I started this thread I was unaware of the MeSCN chlorination approach to making TCT. Garage chemist and I had discussed the other
methos.
I can assure you that I would not have posted the HCN/cyanogen chloride based route at all, but only the MeSCN chlorination, if I had then what
information is on hand now.
Cyanogen chloride combines the properties of HCN and phosgene. The latter is scarier than the former. One of our members recently confirmed this, he
accidentally produced a little phosgene in his lab and can now tell you all about its famous scent. Fortunately he came away with merely a week's
painful asthma-like symptoms, but no pulmonary edema.
Drowning in your own fluids is nature's way of telling you to slow down.
Sic gorgeamus a los subjectatus nunc.
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unome
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Thought these might be interesting... On reacting glycine with 3 equivalents of hypochlorite, researchers have found that it produces cyanogen
chloride ...
It sounds a little far out and not reading Japanese all that well, it is difficult to ascertain whether this could be useful, although there are a
couple of JACS articles that might be of more utility (Mechanism and Kinetics of Cyanogen Chloride Formation from the Chlorination of Glycine & Stability of Cyanogen Chloride in the Presence of Free Chlorine and Monochloramine...
I also threw up the articles in question, as well as a couple of others which might throw some light upon the subject...
Attachment: BreakpointChemistryOrganic.Byproduct.formation.Chlorination.pdf (165kB)
This file has been downloaded 940 times
Attachment: Byproducts.Oxidation.Water.pdf (1MB)
This file has been downloaded 967 times
Attachment: Glycine.Hypochlorite.I.Cyanide.Cyanogen.Chloride.pdf (571kB)
This file has been downloaded 843 times
Attachment: Glycine.Hypochlorite.II.Cyanide.CyanogenChloride.pdf (605kB)
This file has been downloaded 765 times
Attachment: Oxidation.aminoacids.2.cyanides.DAKIN.pdf (462kB)
This file has been downloaded 1041 times
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