Alcl 3 should do the trick as well
If the aim is 9 the temp should be below 0C
If the aim is 8 then roomtemp will do
But cleaning up alcl3 is a nightmare
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Solvents drying with salts or molsieves
Glass drying in an oven or heated jacket
Reagents buying anhydrous
Always gas sparging
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But only in the presence of ZnCl2?
Never heared AlCl3 would lead to chlorination on its own
Im kinda having troubles finding it in first place. Is the paper where it sais it takes 15 minutes for a 92 conversion to d9 is true? 15 minutes? -10C, DCM, Alcl3
Its not clorination, its used instead of PTSA for CBD to THC cyclisation.
I would pre-treat the material with sieves before. This was water in the raw materials that caused the issue. Not from the environment.
Inert gas purging (and making sure that gas is also dry).
When its really sensitive - then I put it in an isolator and make the environment inert and moisture controlled.
No
I am 100% sure that the reaction with alcl3 on dcm makes thc-cl
It s this chloride that can be taken out by activated carbon sinds it s a fairly weak bond reason I say this is that
Once heated at around 75-80C
The unmistakable white fumes of hydrogen chloride are visibly escaping the solution when placing a wet Litmus paper right above the solution it will turn red
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Thats why all ends up in d8 THC durring distillation .
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But isnt it a racemate anyways? I have seen advertised d9 test at 60% d9, but d8 was pure. + price roughly same
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Not understanding your last remark
What is a racimic mixture ?
Wich d8 is pure ?
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Dechlorination is usually performed with strong bases. potassium tert amylate, potassium tert butoxide or NaH are used here for high D9 yield. Dechlorination with KOH in toluene should also be possible, but this would lead to the formation of H20 and I assume this could lead to the formation of D8 again. (But I have no first hand experience here)
In the literature, dechlorination of THC is always performed dry, without heat and in the absence of acids. Those conditons yield high d9.
I doubt that AlCl3 chlorinates the THC. Because in this case a NaOH wash would dechlorinate and we all know that a NaOH wash on its own does not avoid further isomerization at the distillation process.
Maybe it is just one of the nasty aluminum contaminations? 
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Naoh seems to help but there is one base that does the trick completely
Where carbon isn t necessary anymore
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Is an option this step is in the workup and water presence is not an isseu
Unless the super base created is so strong it reacts
Wich I doubt for I have tried methoxide and ethoxide salts as well with no isomerizations occuring
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If you aim for D9:
It will always be a mixture of D9 + X.
All isomerization reactions favor the thermodynamic more stable D8 but every catalyst has a different equilibrium where CBD converts into D9 and at the same time D9 starts to turn into D8.
Under āsimpleā conditions, this is somewhere at 70-80% D9 for AlCl3. If you want to push it further you need to find a balance between
time
temperature
amount of catalyst
amount of solvent
We recently did 2 different runs. One at -10Ā°C and one at 25Ā°C. Results were pretty close to each other. If you use a lot of solvent, like 1:10 or higher, it is much easier to get into the > 80% range. If you use less solvent to get it into production scale, like 1:2, things get tricky. In this scenario you need additives or different approaches. But only adding the catalyst wont get you anywhere close to 90%.
Thats why the chlorination routine is so interesting. Any isomer of THC can be turned into trans-HCL-THC and the dechlorination under above mentioned conditions yields nearly pure D9.
If you aim for D8:
Use pTSA and wait. This is pretty straight forward and no racemat.
Nearly pure D8 
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Correct
1-2 L of dcm yields 65% d9
24L of dcm yields 87% d9
Althoug both will distill to higher D9 #
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Probably in only small amounts deu to no catalyst beeing present
Another thing I find strange is that if after the initial reaction IF some cbd is left say 4% this cbd is NOT affected by any further isomerizations for it s still present after distillation
Wich is akward
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Koh in dmso doesn t do 
tried it
Since dmso is water soluble and easier to get rid of and safer to work with than tolueen and easier to get since tolueen is checked
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I though a mixture of isomers is called racemicā¦
This test I am talking about (being sold as D8) :
20220117-D8THCp.pdf (3.6 MB)
Could it be considered racemic? I would say yesā¦
Racimic means 1 molecule that exists
In each otherās mirror image
Natural extracts are >85% R and <15% S
Isomerized products are 50R/50S
When TIBA or BF3 are used
I havenāt had r and d done on diffrent reagents
This is the reason isomerized product is considered less potent
Since R thc D9 is 3x stronger then SthcD9
It s the last holy grail that needs to be cracked separation of R and S by means of reagents
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Thank you very-very much for your reply. I am not aiming to repeat the experiment in the nearest future. I even rent a lab since my own is purely analytical and doesnāt have RBF over 500ml 
Considering the solvent ratio - also a big thank you. Will look into that. Is that because it makes the conditions milder - thus less d9 goes into d8?
10:1 solvent ratio I can do, but its just the reactor I will be working with is 6l.
Then I guess I would try and source AlCL3 by all means. I read in paper the reaction time is 15 minutes? Its too quick to quickly do an HPLC run. And if i understand it correctly, time is also a crucial aspect, so by the time I get my HPLC results - the isomers ratio will change by a lot.
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