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hexane as nonpolar solvent in extraction

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stormyweathers

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im not sure if this is the right place for this, but here goes:

Why is it that in almost every alkaloid extraction guide, methylene chloride is called as a nonpolar organic solvent?

xylene and hexane are both cheaper, more readily available, safer, and have a lower dipole moment than methylene chloride

are there other factors that i am not realizing?


http://www.springerlink.com/content/r95053t12426g253/

a successful alkaloid extraction using hexane
 
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Well, it's not miscible in water, which kind of does make it a non-polar organic solvent.

I prefer hexanes as a suitable solvent for most really non-polar compounds, but it really depends on what you're extracting -- for instance, caffeine tends to be more soluble in DCM. Sometimes ethanol or methanol will also be better solvents for crude extractions, and then you can go into other methods to purify your target compounds.
 
is there a compiled table of solubilites of psychoactive alkaloids in various solvents somewhere?

or will i have to search for each one individually?
 
I've had great yields using methylene chloride to extract water-insoluble halides. The like dissolves like thing.

Also, it's much easier to evaporate off the methylene chloride.
 
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stormyweathers said:
im not sure if this is the right place for this, but here goes:

Why is it that in almost every alkaloid extraction guide, methylene chloride is called as a nonpolar organic solvent?

xylene and hexane are both cheaper, more readily available, safer, and have a lower dipole moment than methylene chloride

are there other factors that i am not realizing?


http://www.springerlink.com/content/r95053t12426g253/

a successful alkaloid extraction using hexane
Click to expand...

The rule of thumb for solubility is "Like dissolves like". Alkaloids are usually complex structures with both polar and non polar groups, so they dissolve more readily in somewhat polar organic solvents, but not in water. Hexane is very nonpolar, so it would not dissolve most alkaloids, one important exception being N,N-dialkyltryptamines. :) However, for example, hexane will not dissolve bufotenin because of the polar 5-OH substituent. Dichloromethane has a good mixture of polarity that makes most alkaloids soluble and a low boiling point (40 C) that makes it easy to remove. Dichloromethane is actually very low toxicity, so low that for many years it was considered to be nontoxic. Then it was found that if you make rats breath an atmosphere containing 5% dichloromethane vapor for their entire life, a few develop cancer. Chloroform is also a good solvent for alkaloid extraction, but much more toxic, so it has been mostly replaced by dichloromethane. Xylene is also toxic, and can be successfully used for extraction of alkaloids containing aromatic rings, but the high boiling point (ca. 140 C) makes it hard to remove from the goodies.
 
^this is what i was looking for
thanks for the comprehensive answer

so your saying that hexane would be good for a DMT extraction?
on the nexus, i see most people using naptha for that

since naptha is a mixture, i would imagine that its hard to tell its polarity.

however, naptha has a much higher boiling point than DCM


i wish DCM was cheaper.
damn
 
Hexane is pretty useful as a recrystallization solvent though, or a mixture of hexane and acetone, or whatever suits the substrate. I've been trying to goad myself into reading Marcus's The Properties of Solvents, for which the torrent is out there I think.
 
Light aliphatic naphta is usually a mixture of hydrocarbons between 5 and 9 carbons (pentane - nonane). The ratio of the mixture is a big question mark though.

Also a thing to consider is, that hexane is supposedly more toxic than other light hydrocarbons. So use with caution.

Lots of people use heptane for DMT extraction. I hear it's good for recrystallisation, but solubility is lower than naphta. I've always used naphta myself.
 
n-hexane or "hexanes" (which contains a mixture of isomers including n-hexane) is generally considered a health hazard (long term - peripheral nervous system failure) and pentane/heptane/cyclohexane are commonly regarded as safer alternatives used in industrial process chemistry.

As mentioned above, hexane is not nearly as good at dissolving moderately polar molecules compared to more typical extraction solvents (dichloromethane, ether etc.). This can be an advantage if the material you are trying to extract happens to be soluble in hexane, since you can sometimes get a cleaner extraction because many moderately to highly polar organic molecules are not very soluble in hexane.

Pentane/Hexane/Heptane/similar are often used in recrystallization as an "anti-solvent". For recrystallization, you basically desire a solvent or mixture of solvents that will dissolve your compound of interest at higher temperature, but not at lower temperature. This way you can heat up your solution and dissolve everything, then cool slowly to room temperature (or below) and have the compound slowly come out of solution to form crystals.
 
ok then, my bad
haha couldve sword i read that somewhere

if naptha is made up of hydrocarbons 5-9, then why is it better for pulling DMT than just plain hexane?
 
stormyweathers said:
ok then, my bad
haha couldve sword i read that somewhere

if naptha is made up of hydrocarbons 5-9, then why is it better for pulling DMT than just plain hexane?
Click to expand...

it isn't. The whole point of using a weak relatively crappy solvent like hexane or heptane an the like is that it doesn't dissolve the other (more polar) junk in the MHRB. the same applies to extracting cannabinoids from plant material and also pulling the synthetic cannabinoids from spice type drugs for analysis.
Naphtha in all its various forms (petroleum ether) is pretty much the same as a solvent as hexane and 60-80 bp de aromatized petroleum ether can be substituted with hexane and vice versa.
I would like to see the hexane that gets syrupy so that you would notice at the kind of temperatures found in peoples freezers, the stuff melts at something like -100oC and is often used in reactions using dry ice acetone cooling -60 to -78 oC
 
Hexane is metabolised to its diketon which fits exactly into a part of your DNA (I think its on a histidine part where it alkylates). Today its replaced mostly by Heptane.
 
heptane gotcha

i wish home depot stocked solvents like that instead of just MEK, acetone, and naptha

everything else in the store near me is a mix of "petroleum distillates and DCM" so i cant be sure if theyre safe to use
 
Hexane (Zippo ligher fluid) is actually the safest and most effective solvent you could use for non-polar compounds
Coke and DMT love it
 
1) Zippo lighter fluid is essentially VM&P naphtha, which is a mixture of (mostly aliphatic) hydrocarbons. It's not hexane, although there is some hexane in it.

2) Hexane isn't considered particularly safe. Quite the opposite, actually (see above posts by shulgin_jr and hugo24).

3) You have revived yet another old-ass thread without adding anything of value. I tip my hat to you, Sir.
 
Also, avoid use of haloalkanes such as DCM and chloroform, and of course the notorious carbon tet...although good luck ever finding any CCl4 to begin with, its got a reputation to being the 'organic' solvent spawned from hell, avoid using any of them, as according to a journal article, which I will do my best to dig up from the bowels of my collection on beta-carbolines and decarboxylation of tryptophan and impurities...or might have been another one on analytical impurities found in samples of n,n-DMT that found significant quaternization to give the n,n,n-trimethyltryptammonium quaternary salt (as the chloride of course) produced by reaction of the DMT with the solvent.

This is going to be A-inactive, such a molecular beast possesses a charge, and is thus incapable of crossing the BBB, and B-be as such restricted to the periphery to exert unknown toxic effects (I am not saying it IS toxic....but it WILL be centrally inactive and is an unknown with potential toxic properties..which will then be concentrated in the peripheral nervous system) and might just be quite unpleasant, if not actually dangerous.

I recall that rather uncommon little mushroom by the binomial Inocybe aeruginescens, a member of a large family of relatively nondescript gilled fungi notable for having a somewhat radially fibrous cap, and on the whole, reddish, reddish brown to light brown or tan, along with in many of them a potentially lethal concentration of muscarine, a cholinergic neurotoxin (granted one for which almost without par amongst mycotoxins, with the probable exception of giving either kids/animals who ingest Amanita muscaria benzo treatment in hospital to control seizures and the necessity for GABA agonist+pyridoxal phosphate in the far more serious monomethylhydrazine poisoning that arises from either consuming 'correctly prepared' false morels, incorrectly prepared ones, being the poor bastard that has to COOK the false morels on occasion being poisoned by the fumes they give off, or otherwise being in an enclosed space with a large harvest of a mushroom family its a fairly awful idea to pick for consumption to begin with)

Anyhow...this little Inocybe is different, it produces instead of muscarine, some smallish quantities of psilocybin (and/or psilocin, don't ask me the ratio, or if only one is present, which one. I only just woke up, and I'm about to only just go back to bed :P) and as far as it is currently known is the sole producer of the trimethyltryptammonium quat version of psilocybin and IIRC both it, and the bufotenine derivative (bufotenidine is the name of this one IIRC) are quite potent 5HT3 agonists. Central actions of 5HT3r agonists are downright nasty, including nausea, vomiting, anxiety and if not seizure, at least a lowering of seizure threshold. Being a quaternary amine, neither of these will cross the BBB. The peripheral actions aren't much better either, still severe nausea and vomiting and according to wikipedia also acts as an excitatory agent at nociceptive neurons (I.e stimulates pain nerve endings from the sounds of them)

I am not certain that chloroform will alkylate DMT to form the same quaternary ammonium compound that dichlor can, but I wouldn't risk A-wasting DMT and B-turning it into something unknown, but fairly likely to be something pretty unpleasant.
 
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