Why are such huge amounts of solvent and base used?

[MushroomMan]

I looked at a few MHRB STB teks and one of them says to use 1g of NaOH per 1g of MHRB and 15mL of water per gram. This makes no sense to me at all. I don't know how much DMT and related alkaloids are present in MHRB but I'll take a guess and say 5%, that would be 50mg of alkaloids per gram. DMT reacts with NaOH in a 1:1 ratio. DMT has a molar mass of about 180g/mol and NaOH about 40g/mol so in 1g of NaOH there are 1g/40g/mol = 25mmol and the number of moles in 50mg of DMT is 0.05g/180g/mol = 0.28mmol.

So unless I did my calculations wrong, the NaOH is present in a 97:1 ratio to the DMT. Secondly, why so much water? NaOH has a solubility of 1.11g/mL at room temperature. Another tek I looked at uses the same ratio of NaOH to MHRB but about half as much water. I'm new to all this but I'm a chem major so I've done extractions on different compounds before, this is the first time I've seen such excesses of solvent and reagent being used, is there something I'm not taking into consideration here?

 

[5-htp]

Hello MushroomMan,
your calculations are fine and in fact, if you do an A/B prior to basing you would be fine using your calculated amount of base. (this is from reading someone who does it this way)

The ratios given are based on much experience. It's just what works best for most people with each tek. In a STB one deals with a lot of plant matter in which the alkaloids are hidden. It consists of plant fats, tannins, etc.. The excess of base helps to break down the plant matter and to deal with emulsions.

When you extract from other sources as MHRB and there are other alkaloids of interest you will base to a specific ph.

When you do the dryteks, there's almost no water at all

 

[benzyme]

I looked at a few MHRB STB teks and one of them says to use 1g of NaOH per 1g of MHRB and 15mL of water per gram. This makes no sense to me at all. I don't know how much DMT and related alkaloids are present in MHRB but I'll take a guess and say 5%, that would be 50mg of alkaloids per gram. DMT reacts with NaOH in a 1:1 ratio. DMT has a molar mass of about 180g/mol and NaOH about 40g/mol so in 1g of NaOH there are 1g/40g/mol = 25mmol and the number of moles in 50mg of DMT is 0.05g/180g/mol = 0.28mmol.

So unless I did my calculations wrong, the NaOH is present in a 97:1 ratio to the DMT. Secondly, why so much water? NaOH has a solubility of 1.11g/mL at room temperature. Another tek I looked at uses the same ratio of NaOH to MHRB but about half as much water. I'm new to all this but I'm a chem major so I've done extractions on different compounds before, this is the first time I've seen such excesses of solvent and reagent being used, is there something I'm not taking into consideration here?

yea, you're not taking into consideration the pKa of DMT. the A/B extraction is based solely on protonation/deprotonation of the terminal amine, and migration of the free base into a solvent that it's soluble in, that's all.
all that matters is the concentrations of hydronium and hydroxyanions in solution, not stoichiometry like in substitution or addition reactions.

but I do I agree that excess solvents and reagents are used in most of these teks.
and I've never seen 5% DMT from any source, your estimation is grossly exaggerated.

never done a dry tek, but I don't trust them for the simple fact that acids and bases
require a minimum volume of a polar solvent (typically water) for dissociation to occur

 

[acacian]

go A/B if you wanna avoid using so much lye... i get away with 6g in mine added to a 500ml solution. cheaper and less disgusting/hazardous

 

[MushroomMan]

5-htp: Ah yeah, thats something I didn't consider, the fact that there are more than just alkaloids that will react with the NaOH. The same problem will exist with acids though. As for emulsions, you could also deal with them with salts like NaCl, that would also help salt out the freebase DMT from the aqueous layer. Sounds like A/B is the way to go but have you ever tried it with a Soxhlet? If so, what solvent do you use? What I'm really wondering is whether the alkaloids are naturally present as freebase or salts. Maybe the pH of the soil in which the MH tree grows plays a role in determining whether the alkaloids are present as salts or freebase.

benzyme: When I said 5% it was a wild guess. I'm new to all this. What would be a realistic estimate for MHRB? Yeah dissociation of acids and ionic bases can only occur in adequately polar solvents. I believe that 98% H2SO4 is less hazardous to handle than slightly more dilute solutions for this reason. I bet strong organic acids like TFA or methanesulfonic acid can dissociate better on NP solvents though. Do dry teks use only NP solvents? I'm not sure about acetone but I know from experience that dissociation occurs in ethanol, although to a lesser extent than water.

acacian: Yeah I'm gonna go the A/B route instead. Does vinegar work? It works well with iboga RB. I read that DMT has a pKa of 8.6 and ibogaine 8.1 so I suspect vinegar should be enough to convert the DMT and related alkaloids into their acetate salts.

 

[5-htp]

5-htp: Ah yeah, thats something I didn't consider, the fact that there are more than just alkaloids that will react with the NaOH. The same problem will exist with acids though. As for emulsions, you could also deal with them with salts like NaCl, that would also help salt out the freebase DMT from the aqueous layer. Sounds like A/B is the way to go but have you ever tried it with a Soxhlet? If so, what solvent do you use? What I'm really wondering is whether the alkaloids are naturally present as freebase or salts. Maybe the pH of the soil in which the MH tree grows plays a role in determining whether the alkaloids are present as salts or freebase.

I never did salt with NaCl, the NaOH just works fine for me but I will do so when I start extracting from Syrian Rue, performing the Manske to precipitate Harmala HCl. I never used a Soxhlet because I simply don't have one. The best setup I used for extraction was a 2 Liter Simex Flask placed on a magnetic stirrer/hotplate combo set to around 50°C with little stirring. Worked like a charm and was my first and the best spice I got yet. I used to perform small pulls with Toluol, Hexane or Naphtha using a pipette. There wasn't even the need to use the sep funnel because the method is really good working. I think in MHRB the alkaloids are probably in the salted/tannin-form.

 

[benzyme]

I bet strong organic acids like TFA or methanesulfonic acid can dissociate better on NP solvents though.

save the TFA for more useful things, like gradients for LC-MS; and no one uses sulfuric for a/b, maybe to salt out mesc extractions from xylene. sulfuric doesn't tend to do any dissociation in xylene.

people use dilute acetic acid, or hydrochloric acid. polyprotic acids tend to complicate things. DMT is 99.96% fully protonated at a pH of 5.2, and equally deprotonated at 13.6.

soxhlet is a waste of time, use physical methods to lyse the plant cells to get the alks in
dilute acidic solution. that's time better spent.

 

[DMTripper]

I don't use any instructions when I extract. Just do it how I feel works best. I tend to use quite a lot of water. I do two boils on the bark with a little acid. And then I boil that down. I like to filter the bark away and work only with liquids.

And the reason for so much lye is the emulsion. If you have a lot of emulsion then you can just add lye and it separates much better.

And last time I got over 2% yield of light orange/pink spice ready to vaporize.