Carboxylation - Adding the "a" back to THC


@Future. Thanks for the summary.

the sugar attached to the free alcohol was not a suggestion for attaching the carboxyl group. it was the reason @Photon_noir was chastising us for wandering.

It was suggested as a way of attracting cannabinoids (now cannabosides) to each other for the purpose of purification via crystallization. with THC-gluc crystallized (and thus isolated). one could perform the required REcarb step(s) on 99+% purity and be less likely to make junk.

the paper I linked uses enzymes to add the sugar(s). with the goal of increasing water solubility & thus bioavailability. my chemistry was a loooong time ago.

Edit: mind you, after being chastised for wandering, I went back and read the thread a 1/2 dozen times. It hangs together. just. With THC-acetate thrown in there as a red herring for 10100 to get a hold of.


What if one was to use a (de)carboxylase enzyme? @Shadownaught


As suggested in this paper?


one could certainly be evolved for the task in short order. the enzyme they used looks like it’s target is close enough structurally to use as a starting point.

you amplify the gene (PCR) under low fidelity conditions, and look for clones that decarb our favorite cannabinoids.

I’d wager an enzyme would be the most regio-specifc way to put the carboxyl back too. the best candidate from above might be a good starting point, under different reaction conditions, but screening through the first pool as well makes good sense.

If I could see a good way to make decarbing/REcarbing THC a life saving (and thus selectable) trait, it would be faster.

Edit: …and now we’re officially off topic. thread title is “Chemistry”!!


@cyclopath actually OP asked about carboxylation, so I edited the title to match and hopefully draw in more conversation


Yes sir this sure does make more sense. However sterically hindered by the alcohol group on the phenol ring and the carbon chain it is the only active site possible on that ring to attach a carboxyl group. I was thinking use some ortho/para directing groups for this reaction to even be feasible on paper.

I think this is a silly method in general to solve the problem at hand and there should be other synthetic methods to solve this problem than adding back on the carboxyl group!

Thank you for the input and thought. Let me know how you feel about the directing groups


Attaching the sugar would possibly allow for decarbed thc to be able to form a crystal.

If anyone has schlenk line chemistry they would like me to try this on :wink: :wink: :wink:

I would also like to try with sulfate/phosphate groups.

Future! Your Kolbe Schmidtt probably wont work, my guess is that the carbon ortho (adjacent) to the free alcohol would be sterically hindered by the alcohol/carbon chain even with the lowest pka on the thc molecule! Im down to try tho if someone has some schlenk lines for me to use!

There is possible chemistry that does not involve expensive enzymes i just dont have my academic lab at my disposal to next fall :frowning:


and this is why I don’t do organic synthesis!

As a thought puzzle it is an interesting discussion but I agree that this is a long way to go to get a cup of coffee. Isolate the THCA before decarbing, the end.



@cyclopath, I did not mean to sound chastising. It’s an open discussion, and open discussions around organic chemical synthesis tend to be this way. No harm, no foul.

@QGA That opens a new can of worms trying to attach things to specific sites (same as y’all are trying to do with the carboxylic acid) would have to somehow be easier than adding the COOH directly, and I don’t see how it could be. Regioselectivity in this case would prefer THCa type B (COOH para to the OH, rather than the naturally-occurring THCa type A with the functional groups ortho to one another).

This may interest you to the ends of which you speak:

Phenyl Rxn Director Groups


yes you definitely can attach the de-carboxylation back . just need to find the right positional group and the right mixture of various sugar moieties that will enhance various polarity of the the functional groups to make them “active”. Once they are “activated” then the de-carboyxlation can be back added into the area of your choice


Please do not spread misinformation on this site to try to push your own sales agenda.


why would you say that?

where did we say we are trying to sell something? did we offer something for sale? This is a site to exchange ideas. we only expressed an idea. You dont allow that?


I do not know why @QGA thinks you are trying to sell something, but I do understand why he thinks you might be spreading misinformation; your mention of sugar doesn’t make a lot of sense the way you are explaining it. Can you please elaborate and/or provide a link to a study regarding this method?


Funny-CGA mentioned the same thing I did-which is using a sugar


I apologize for any misunderstanding in my statement. I will try to refrain from commenting if you feel that I am misrepresenting or saying something incorrect. I have 30+ years of experience in organic synthesis chemistry. I am merely here to try and exchange information and ideas. If there is something I have said that is incorrect I welcome your feedback. I would appreciate a more civilized exchange without accusations.


I think you’re fine, but I would like you to explain what synthetic route you intend to use involving sugar and re-carboxylating THC. @QGA was saying that adding a sugar moiety to the THC molecule instead of the carboxylic acid, just to give the THC the ability to crystallize, if not also make it water soluble. His mention of adding a sugar molecule as a large functional group had nothing to do with adding a carboxylic acid group… except that either one will allow THC to crystallize.


The guy is just regurgitating information on this post, nothing novel. 80% of @DrJosh posts are trying to sell Chinese manufacturing equiptment. That is where my accusations arise from.


QGA we do not sell Chinese equipment and I am not sure where you get your ideas from? what do you sell or make? Besides making stuff up.


@DrJosh @QGA Okay guys, I understand your criticisms and you have the right to express them and defend yourselves against them. I believe that has been effectively explained and done here. I do not personally know either of you, but you are both generally respectful and respectable people from what I have seen. I appreciate your explanation of your intolerance of @DrJosh, @QGA . I feel that English is not your first language @DrJosh , and that may be a source of misunderstanding through no fault of your own. Please accept my apology if I am incorrect in this belief.
I do not know the site policy on advertising equipment, so perhaps @Future could explain.
In any case, I am fairly certain that intentional disinformation is not tolerated here, so if anyone is doing that, I request that you cease, immediately. Unintentional misinformation is a common problem, and is not to be attacked here, but instead respectfully corrected, if possible.
Since there is obvious disagreement of opinion, and as I am uncertain of the facts due to lack of evidence presented here, I would ask that you simply ignore one another and refrain from public attacks of character. Instead, please direct your grievances to me, @Future or @sidco in private messages, from which we can investigate the accusations and discreetly put an end to any genuine problems.
Thank you, both! :v:


Advertising equipment sales is allowed in the classifieds, advertising yourself and business is allowed in the proper sub category as well.

@DrJosh do you have a link to another industry using sugar to do as you claim?


Public Reminder.

Don’t spam. Be specific in why and how your equipment would apply to the OP (aka be helpful)

Can confirm. In thread is not the place to handle ‘issues’ of a personal nature. If the post doesn’t have anything to do with “Carboxylation - Adding the “a” back to THC” do not reply (including to this reminder please and thank you). Look forward to a short and simple

Thanks all.