The Hive > Tryptamine Chemistry

why use a solvent at all?

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indole_amine:
Sure you can! (at least with SnCl2, stored over CaCl2 at room temp for several days...)

And why use a solvent at all? Molecular sieves work fine for drying gases; and all drying processes rely on the fact that crystal water is always given off as soon as the drying agent's hydrate bond represents a less energy-consuming type of bonding compared to the substrate, meaning that the drying agent has a greater affinity for water than the substance to be dried, either alone or with the help of vacuum and/or heat (which both make it harder for the water to stay in the crystal lattice, therefore it leaves at some point..). Bonus: ions have a hard time wandering through air, not to speak of vacuum. I doubt that any reaction between the drying agent and compound to be dried can take place in a dessicator.

Mol sieves further work a lot better if heated, so I don't see why you would want to expose any ergot compound to the possible danger of destruction, just to be able to dry it together with some solvent... ::)

Maybe I should've asked "why in any way should a solvent be better in terms of transporting the water to the sieves, compared to plain air having a pressure of

Bubbleplate:
Drying agents like Magnesium Sulfate or Calcium Chloride.
Molecular Sieves are crystalline metal aluminosilicates having a three-dimensional interconnecting network of silica and alumina tetrahedra. Natural water of hydration is removed from this network by heating to produce uniform cavities which selectively adsorb molecules of a specific size. So, for example, Type 4A Sieves will selectively absorb H2O molecules and leave behind larger molecules such as Lysergic Acid. Very little, if any, loss of LSA should occur.
I guess my original question should have been, which solvent would be the best "substrate" to dissolve LSA in order to have the Molecular Sieves suck up the H2O and leave behind dry LSA...

indole_amine:
I know about mol. sieves, and I know that they're fairly inert in most cases. (this excludes strong acids and bases for example, as well as ethanol). But why not use air as transportation medium? Sieves were originally designed for quick gas drying during oil refining processes AFAIK. And halfway evacuated air is pretty damn inert to almost everything, believe me.

Anyway: DCM can take up quite a lot of water, so this might be the solvent of choice, or ethyl acetate maybe - and diethyl ether should work fine, too. Maybe you can even use plain methanol, but I'm not sure about moderately polar solvents - only about the inertness of the mentioned nonpolar solvents.
Not suited would be for example cyclohexane or benzene, as their maximum water content is fair too small.

But you should consider that you can do more damage to your precious molecule if you dissolve it in a solvent. And: the advantage of using air as the drying medium is that you can apply vacuum. Which helps a lot in drying! Try that with ether... :P


indole_amine

Lilienthal:
indole_amine: the water sticks in the crystal structure and will NOT crawl out there, at least not in reasonable time and without heating it up!

Bubbleplate: I didn't say that lysergic acid could be absorbed like water to the sieves, I was talking about unspecific binding, similar to the adsorption to silica gel. I'd guess that the more polar the solvent the less likely is such adsorption.

I suggest that everybody rereads the whole thread again before posting redundant or wrong stuff...  :)

indole_amine:
indole_amine: the water sticks in the crystal structure and will NOT crawl out there, at least not in reasonable time and without heating it up!

Exactly - you have to create conditions which allow for the water to be given off; these include applying heat, diminished pressure and a drying agent - all cause the water to leave the crystal structure with more ease, because the gaseous state (and/or being bonded to the drying agent) require less energy and therefore this are more desirable states for the H2O, and so it leaves the crystal matrix.

Why should the water leave the crystal structure more easily when a nonpolar, hydrophobic solvent is used, without any heating and/or vacuum?

(I always said vacuum + heating + sieves + dessicator, not only sieves alone - didn't I?)

Is there any error or redundance?


indole_amine

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