What happened to my THC content? Lab says conversion into delta10. How?


@Lewis_Bronsted; How do you propose genetics might affect isomerization upon distillation?

Do you have specific cleaning techniques you suspect might be involved?

Or are you theorizing a lack of cleaning?



Wow that is a really bad chromatograph. I count at least 3 unresolved peaks, all in what I suspect are isomerization products. Also, I would be very concerned with a lab using what ever method they are running on that hplc. It looks like they are trying to run a very fast method (2 min!), Which makes me think this is a uhplc, but they are not capable of separating isomers at all with what ever method they are running. Is this a ISO or state certified lab? That method does not look like it would pass basic quality control.
I do not know of a hplc method where CBN comes of after d9 and d8, ask them the run conditions/gradient and report back, not that it really matters but it looks to be a really non-standard method, which makes me think the lab maybe doing alot of other stuff in …interesting ways.

I would never accept a trace from a lab like that. It needs to be re run at least at a 1:4 dilution and separate the co-eluting peaks, but I am sure you have cooked distillate there.

Basic forensic question for cooked distillate.

How long did the cannabinoid pass take?
What temp range did the cannabinoids come over at?
What was your pot temperature?
What arangement? SPD, wiped film, spinning band?


You want the surface tension broken but not violent on an spd, idk about a BR. Too much stir bar can kick stuff up into the head I’d think. Just a guess though


Dr. Jack,

Can you cite the literature you are referring to for base catalyzing the reaction? In our work, we have not seen this, and it is a purely thermal driven reaction.

Actually, I think there is far more going on in the isomerization department during distillation than most currently understand. Cis/trans isomerization around sterocenters is the first step, then d9/d8, then d10/d10a and the rest. Each step creates more and more of a bell curve of THC isomers. Acid or base might favor on reaction path over another, but I don’t think either are necessary. Using data from current 3rd party labs is useless, specific enatiomer methods need to be utilized.

The other issue is oxidation to the enol form. This is happening to a large % of the extracts out there(not just distillate), is not being detected by current methods, and is most definitely effecting the pharmakinetics. I think the two reactions are happening in conjunction with each other.

If you have NMR access on the regular let me know, maybe we can collaborate on a few projects.


There are alkaline compounds produce by cannabis too, for example propylamine is a major contributor to smell. Terpenes are a major component but I’ve been frustrated for years at how primitive cannabis fragrance formulations are; there is so much more than terpenes! So generally plants are always slightly acidic bc otherwise, just like hydronics, most elements would be locked out. So it’s possible and should be considered, but it’s a tiny stretch

I’ve used some crazy oxidants - none of them alkaline that I can think of - to clean glassware, especially when there is charring from high heat distillation. I’d assume they would make CBN not delta 10 but there are alkaline oxidants etc, plus even a lye solution may be required for certain choads.


Enol is a tautomer of keto, do you mean an enol ester perchance? It’s certainly possible to isolate some enols but the carbon carbon double is so much less stabile than a C=O …

For the record, this thread is bananas… but if a base isn’t needed to catalyze this isomerisation then it makes a little more sense. For the record I’m not sure what was found, but simple heat degradation would make a lot more sense than what’s been proposed.


You mean this?

The keto form of the phenol on the C-ring?


Ok, so to be clear, THC D10 is the ketone analogue above? Going from the alcohol to the keto is definitely an oxidation… also in ethanol you would see the ethyl enol ester. Oxidizing thc further makes cbn, and I see that’s pretty high in the analysis above.

Air is a chemical that’s not needed during distillation …

(1) proper insulation is better than more heat
(2) sparge (Firestone valve)


Whats a sparge ?:grinning:


It’s a technique also know as de-gassing. You pull a vacuum, blanket the vessel with an inert gas, and repeat the cycle until you remove every atom of air.

Usually schlenck lines are advised, but I think that’s overkill, bc just degassing is pretty overkill. A firestone valve is still pretty expensive but it’s facile to use and minimal.


We purchased the 28x70 pill stir bar as well as the 24x50 stir bar and they both loose magnetism at about 500rpm. Is there anything I can do to speed them up? Is there something im missing with the type of stir bar to use?


Hi Lewis,

I actually drew that to try to clarify what people were thinking. The double bond in the in the C ring is the position for d9. I don’t think it’s likely at all because I’m not sure one can easily destroy an aromatic system to tautomerize a phenol into its keto form. But it is also not an oxidation process, keto-enols are tautomers. I find this first explanation adequate:


This mystery d10, or d10a-6a puts the C ring double bond next to the A ring, so that there is a more conjugated system. Ignoring any discussion of sterics it would be more stable thermodynamically due to the longer conjugation system. If you look at

d10 is there under the CBD section. Quite a good paper.

I will be at Emerald conference in a few days and will pry the answer from someone. Someone has the standard and/or the MS and UV-Vis data, and probably even the NMR data on these isomers by now. I would assume a scientific communication is forthcoming on this mystery.