Soxhlet Question

[Nathanial.Dread]

If I had a soxhlet, could I extract with a mixture of ddH2O and acetic acid (pH ~ 4)? I looked at some older topics, but couldn't find any kind of confirmation.

The acid should travel with the solvent, meaning that the bark/leaves/whatever was getting extracted directly into acidified water.

Then do usual A/B.

Blessings
~ND

 

[Mindlusion]

You could.

Typically you wouldn't want to use a mixture like that (5% acetic acid). Even though it doesn't form an azeotrope, acetic acid is volatile enough and close enough to the b.p. of water that it will still work. (its hard to concentrate acetic acid by boiling or distillation, you need a very tall column).

Though, It would be much easier to use something like ethanol in the soxhlet. Make a crude alcoholic extract which you can distill off the ethanol, then do the A/B on that crude extract.

It is extremely effective in reducing the material you have to work with, and alcoholic extracts of natural products in a soxhlet will almost always give you quantitative yields.

I don't know about acetic acid, it may work just as well but could take a lot longer.

 

[Nathanial.Dread]

Thanks for the insight.

Do you have any off-the-cuff guesstimates as to what the minimum usable %EtOH would be? Everclear would be much easier to get a hold of than trying to track down anhydrous EtOH or distilling my own.

Would you acidify the EtOH solution in the soxhlet? If you could, it would basically save a step, you could treat the product like you were going STB (if I'm understanding this right).

Blessings
~ND

 

[Mindlusion]

You don't want to use anhydrous in a soxhlet, its better used for other applications. Its going to absorb a bit of water anyway.
you want to use azeotropic. (about 95%) <-- that is everclear i believe.

No need to acidify, the ethanol will extract everything by itself. You are going to need to remove the ethanol by distillation or evaporation after the soxhlet extract. You can't treat it like water and add base, either. The freebase is soluble in ethanol anyway.

 

[blue.magic]

I think you have to use some other acid then acetic in your EtOH solution as acetic acid and EtOH form ethyl acetate (?).

I found some people don't even use acid at all for initial extraction. It may not be necessary for alcoholic extract as DMT freebase is soluble in ethanol. Ethanol will therefore pull both DMT salt and freebase. If you really want/need an acid step (e.g. for de-fatting), then you can mix your alcohol extract with acidic water, distill off the ethanol and continue with A/B extraction as usual.

I never tried that, but this method is described in one cactus analysis thread and works very well for mescaline.

 

[downwardsfromzero]

I think you have to use some other acid then acetic in your EtOH solution as acetic acid and EtOH form ethyl acetate (?).

Very little ethyl acetate will be formed from mixing just ethanol and acetic acid without adding a strong mineral acid catalyst or a suitable reagent system to absorb the water which is also formed in the esterification reaction.

I found some people don't even use acid at all for initial extraction. It may not be necessary for alcoholic extract as DMT freebase is soluble in ethanol. Ethanol will therefore pull both DMT salt and freebase. If you really want/need an acid step (e.g. for de-fatting), then you can mix your alcohol extract with acidic water, distill off the ethanol and continue with A/B extraction as usual.

I never tried that, but this method is described in one cactus analysis thread and works very well for mescaline.

From what I read in the posts preceding yours, the choice would be either/or, rather than both, with the greatly preferred choice being 95% ethanol. Do you have a link for the acidified ethanol cactus extraction? Is it any better than using plain ethanol?

 

[blue.magic]

From what I read in the posts preceding yours, the choice would be either/or, rather than both, with the greatly preferred choice being 95% ethanol. Do you have a link for the acidified ethanol cactus extraction? Is it any better than using plain ethanol

Here: Mescaline quantification in live cacti using TLC.

See the attached PDF file, step 9). The actual tek is in the second half of the document.

The initial extraction is actually done in basified ethanol (since freebase mescaline is said to be more soluble in ethanol), then transferred to acidified water and then filtered.

I guess the water phase is added to remove water-insoluble impurities (there is quite a lot of them depicted).

So the benefit of using two solvents (EtOH, H20) is the opportunity to remove more impurities. I am not sure how that applies to DMT-containing plant material used by OP.

 

[downwardsfromzero]

Thanks. The document is describing development of a tlc plate, though.

9) After spotting, the plates are eluted with Bunk Police’s eluens. I think it’s 100/2
methanol/ammonia (24,5%).

That's rather different from a primary extraction in a soxhlet. Ammoniacal ethanol might be a way to go for cactus extraction but you'd need really good containment to prevent all the ammonia escaping during the several hours of reflux. Ditto for DMT extraction.

 

[blue.magic]

Thanks. The document is describing development of a tlc plate, though.

9) After spotting, the plates are eluted with Bunk Police’s eluens. I think it’s 100/2
methanol/ammonia (24,5%).

That's rather different from a primary extraction in a soxhlet. Ammoniacal ethanol might be a way to go for cactus extraction but you'd need really good containment to prevent all the ammonia escaping during the several hours of reflux. Ditto for DMT extraction.

No, that's the TLC part - look at the second part of the document, where is the actual extraction tek.

It's the second half of the PDF.

 

[Ulim]

I think you have to use some other acid then acetic in your EtOH solution as acetic acid and EtOH form ethyl acetate (?).

Very little ethyl acetate will be formed from mixing just ethanol and acetic acid without adding a strong mineral acid catalyst or a suitable reagent system to absorb the water which is also formed in the esterification reaction.

Thats true. If you have high water content the equilibrium will be shifted towards EtOH and acetic acid.

Iirc its like 60% ethyl acetate at room temp if you just mix 99% acetic and 99% EtOH.
The acetic will catalyze itself but rather slowly.
Also i dont expect that to even be bad. Ethyl acetate is a good solvent too.

 

[downwardsfromzero]

No, that's the TLC part - look at the second part of the document, where is the actual extraction tek.

It's the second half of the PDF.

Oh, so it is - I've no idea why last time I looked only the first half of the document was visible.

It's a lovely piece of work that document. The crude extraction should work as a general method but the workup would have to be tuned to whatever the target compound might happen to be.

 

[blue.magic]

No, that's the TLC part - look at the second part of the document, where is the actual extraction tek.

It's the second half of the PDF.

Oh, so it is - I've no idea why last time I looked only the first half of the document was visible.

It's a lovely piece of work that document. The crude extraction should work as a general method but the workup would have to be tuned to whatever the target compound might happen to be.

Yes I plan to reproduce the extraction for mescaline, but now researching how to employ similar process for MHRB.

Some say to use just ethanol, some basic ethanol and some acidic ethanol.

Why not to use say ammonia + EtOH for extraction. After Soxhletation, one need to just pull with nonpolar and then either freeze precipitate or backsalt.

Alternatively, one may soak the root bark in minimal amout of basic water, dry and transfer to Soxhlet for alcoholic extraction.

I guess the whoel point of acidic extraction is the opportunity to defat, right?