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Harmala Alkaloid Solubilities:

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Mydriasis

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Here's a thread for people to try different solvents and what they are good for.

I'll kick it off ~

Naptha: 20mL's to 0.4 grams of impure harmalas pulled 'trace' amounts of a contaminant. Slight yellow residue, not a good solvent.

Ethyl-Acetate: 20mL's to 0.4grams of impure harmalas, the solvent turned orange. Definitely works as the journals say it does. Though I don't feel like it pulled everything. I'll post more quantitative results tommorrow I guess, but the point is they are soluble.

Recrystallisation:
One's I have not yet tested but are posted in literature(from Purification of Laboratory Chemicals 5th Edition):
Harmaline (7-methoxy-l-methyl-4,9-dihydro-3H-~-carboline, 4,9-dihydro-7-methoxy-l-methyl-3H-pyrido[3,4-b]indole)

[304-21-21 M 214.3, m 229-230°, 229-231°, 235-237O(after distn at 120-140°/10-3), pK1 4.2. Recrystallised from MeOH and sublimed at high vacuum. It has, 218, 260 and 376nm (log E 4.27, 3.90 and 4.02 respectively);

IR (Nujol) v 1620, UV in MeOH has,1600, 1570 and 1535cm-1and in CHC13 v 1470 and 1629cm-I. [Spenser Can J Chem 37 1851 1959; Marion et al. J Am Chem Soc 73 305 1951;

UV Prukner and Witkop Justus Liebigs Ann Chem 554 127 1942.1 The hydrochloride dihydrate has m 234-236O(dec), the picrate has m 228-229* (sinters at 215*) from aqueous EtOH, and the N-acetate forms needles m 204-205*.
Click to expand...
.

Harmaline/Harmadine:
...On recrystallization from methanol/benzene it formed slender needles which melted at 199*C.
Click to expand...
S. Siddiqui, Pakistan J. Sci, Ind. Res., 5, 207 (1962).

If anyone else has further information please share :).
 
That says the picrate of harmaline can be recrystallized from aqueous ethanol. I really strongly recommend against kitchen chemists playing around with picric acid. If you're sloppy or don't know enough about what you're doing, you could easily have a very large unpleasant explosion on your hands (when picric acid dried out, it's a pressure-sensative explosive)
 
Yes, people here should def not be messing with picric acid, and as I said before dorge, I do think that acqueous ethanol will dissolve harmalas but the question is how much water and what temperature. Also notice this is for the final crystallization, when most of the impurities were already removed. Direct acqueous ethanol soak in plant matter might pull a certain amount of impurities which could be unwanted, or it might pull too little alkaloids at low temps/small water content. Would be wonderful if we could test this directly. I would also love to know exactly what salt form harmalas are naturally in plant form.

Thanks for the thread myd!

Dorge, I hope you are just trying to point out things to me with good heart and not somehow 'competing' as if Im saying something doesnt work and you're trying to prove it does, because thats definitely not my intention when I put the harmala solubilities to question. Im just looking for the best most effective methods and for making nexus info reliable, and hoping my questions serve for others to take as a starting point for their own tests, collaboratively enhancing our knowledge. I have no vested interest in any one or other side of the discussion :)
 
Oops good call Entro! Yea those NO2 groups hold a lot of energy. Not good! I just got all excited seeing the n-acetate when skimming through. I'll try not to make that mistake again.

*Updated the recrystallization solvent with reference in OP.*
 
1 gram of mixed freebase harmalas was stirred into boiling 30mL of ~95% isopropyl alcohol. Slightly soluble, still alot remaining at the bottom.

1 gram of mixed freebase harmalas was stirred into 30mL of boiling dry acetone. Slightly soluble still a good deal remaining undissolved.

Waiting for these to evaporate to conduct more tests...

- Toluene/xylene/benzene seems like the best bet for re-x.
 
SWIM has tried all sorts of solvents for freebase harmalas; methanol, ethanol, IPA, acetone, xylene are just not good enough. DCM and chloroform are the only way to go.
 
@infundibilum, thanks for the tip. It's a good thing chloroform is relatively easy to come by. My only problem with it is it's short-shelf life and tendency to evolve phosgene. Not exactly friendly for at home experimentation.

They certainly do have limited solubilities in most common solvents. A lot of papers use Ethyl acetate which I also find surprising, as its not very efficient in my experience. It's miscability with water is troublesome as well.

DCM sounds nice. I'll have to look into that soon. Need a bleed tube for solvent ripping before that can happen though.
 
I've done a couple of caapi extractions with IPA and methanol. Both produced disappointingly low yields. I wonder if it has something to do with harmalas solubility.

First extraction:
1. IPA extraction in a Continuous Solid-Liquid Extractor (CSLE). Takes 2-3 hours. I stop when the solvent filtering through the powder is completely clear.
2. Drying the extract.
3. Dissolution of the crude extract in diluted H3PO4 (pH~3.3).
4. Decanting and filtering the liquids. Solids are still kept.
5. Basifying the liquids with lye to pH~12.5.
6. Vacuum filtering, washing with water, drying and collecting the solids.
Yield - 0.26%.

Second extraction:
1. Methanol maceration for 4 days.
2. Methanol extraction in CSLE.
2. Drying the extract.
3. Dissolution of the crude extract in diluted H3PO4 (pH~2.7).
4. Decanting and filtering the liquids. Discarding the solids.
5. Basifying the liquids with lye to pH~12.5.
6. Vacuum filtering, washing with water, drying and collecting the solids.
Yiled - 0.164%.

In the 1st extraction I used Diatomaceus Earth, so I suspected that it may have trapped most of the alkaloids. After the second extraction I can see that this is not a problem because I did not use it. Also the second time I used a more efficient solvent (methanol) and added maceration.

I am a reasonably experienced extractor, so there were no major screw-ups. All chemicals used were of lab grade. IPA and methanol concentration was not measured.

At the moment my 3 probable culprits:

A. Poor extraction of harmalas by undiluted alcohols.
B. Poor phosphates solubility, therefore they may have been discarded with solids.
C. Bunk caapi.

I would appreciate your ideas.
 
Trickster, I don't understand why you don't use water for the salts. Harmala salts are very soluble in water. Not to mention I can say with 90% certainty that on evaporation of harmala alkaloids in alcohol oxidation occurs. Although some believe the science I used to test this hypothesis is inconclusive(which is completely fair).
 
Mydriasis said:
Trickster, I don't understand why you don't use water for the salts. Harmala salts are very soluble in water.
Click to expand...

With mhrb I've polished alcohol extraction tek almost to perfection. It is very energy efficient. I manage to recover most of solvents. It produces consistently great yields (1% and up). The final product is so clean that I don't have to re-x it.

I do not use water because it clogs extractors (Soxhlet and others). It also requires much more heat. I use alcohols only for pre-extraction. Once the plant material is discarded I proceed with the standard A/B extraction as usual.

Now I am trying to adapt this tek to harmalas.

In most magazine articles about harmalas extraction researchers use MeOH. I do not think they're stupid.

Mydriasis said:
Not to mention I can say with 90% certainty that on evaporation of harmala alkaloids in alcohol oxidation occurs. Although some believe the science I used to test this hypothesis is inconclusive(which is completely fair).
Click to expand...

This still needs to be proven. MeOH boils at much lower temp then H2O (65C instead of 100C), so overheating is less likely. There seems to be no chemical reaction between harmalas and MeOH, So where do harmalas get oxygen atoms from?
 
I said on evaporation. Here do a quick test for me. Put maybe a gram of white harmalas into sayyy, 20ml of hot acetone or isopropyl alcohol in a small evaporating dish. They won't fully dissolve that's cool. Let the acetone evaporate. Check to see what color of ring you get on the evaporation dish. 😉

edit - also it is to my understanding the freebase compounds I believe it was Harmine has a greater affinity for Methanol, while I believe it was Harmaline has a greater affinity for say benzene. Forget the paper, but they mentioned a separation of both compounds doing fractional recrystallization using this binary solvent system.

It may be energy efficient, but how efficient is it really, if it's only producing 1/5 of the accessible yield using water?
 
That depends on the salt you want to use. Harmala acetates are very soluble. You could probably fit over 100 gram of harmalas in 100ml water. Fumarates isn't very soluble. Don't remember exactly, but I don't think 1 gram harmala fumarates will dissolve in 100ml water.
 
I've prepared lots of pure freebase Harmalas, and want to grow nice salt crystals. Dissolved some of that in white vinegar and left it to evaporate, to my wonder a yellow resin remained after evaporation (the resin residue must have been in the white vinegar), this time I want to try with residue-free dilute HCL acid. Wanted to know the solublity to add the minimum needed liquid for faster evaporation.

The vinegar-harmala solution was not transparent (because of that resinous junk?) and I couldn't see thru it to know if all the freebase was dissolved or not, perhaps the HCL-harmala solution will be transparent?
 
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