Unknowns In Isolate Conversions

nope.

p = -log
H = c(H3O+)

I could be, but with the kindergarten level tantrums @artisanextracts is throwing, i choose not to be. This is all absolute n00b level shit that is exhaustively documented in very simple language on Wikipedia, and as such should be read up on there.

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If the acids aren’t creating hydronium in an aqueous solution, are the H+ even freely moving around or are they still stuck to their respective molecules.

Also, even if an acid is non-volatile, isnt there potential that it is entrained in your vapor flow as a liquid

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Remember, in an organic context “acid” doesn’t universally mean “adds protons” to the solution. It can also mean “takes electrons” from the system if I remember my O chem correctly (Ie Bronsted vs Lewis acids).

IMO @roiplek is being unnecessarily pedantic over the definition of “pH” since pH is just measuring protons to characterize the higher concept of the electronic (as in literal electrons) activity of the solution.

Hell the pH probes everyone uses works by measuring electrical conductivity compared to known pH standard solutions.

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If there’s no hydrogen’s leaving the molecule of the acid, how do can one expect the electrons to be “taken”?

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Well there is pH, but what your are refering to here is the redox potential often noted Eh or pe.

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If you’re referring to the particular instance of using Tosic Acid to isomerize D8, yeah there’s plenty of hydrogens flying around there. I’m just making a nerdy chemistry point.

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Here’s a small piece of what your wikipedia reference states numb nut. You are nothing bet a troll.
potential of hydrogen

In chemistry, pH (/piːˈeɪtʃ/, denoting ‘potential of hydrogen’ or ‘power of hydrogen’)

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In the case of lewis acid, electon doublets and hability to form covalent bond are considered, with no change in oxidation state. Thus this is not a matter of electron activity as with redox reactions. Still I don’t know how to define the activity of a lewis acid in formal equations… :thinking:

I believe everyone here have some valid points.
What is fundamentally dealt with is the acidic/neutral/basic character of an organic mixture. There are different concepts. One could also refer to nucleophily versus acidity… since cannabinoïds can undergo protic conversions, and some have alcool and/or acid groups, even with very limited actvities, perhaps one could consider that cannabinoïd mixtures are kind of protic solvents (can dissolve PTSA for instance), and thus that the concept of pH can be applied.

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Your definition falls within a realm of highschool chemistry. Once you get into higher education in chemistry (or most sciences) you essentially need to unlearn everything and relearn it in a more robust context. “Power of hydrogen” isn’t synonymous with pH in a proper context unfortunately, although it is certainly a nice helpful functional thing, albeit a bit basic

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5 posts were split to a new topic: Artisanextracts and roiplek, first date

Sure, and it doesn’t even matter much if it’s a solid or liquid. Given sufficient movement of liquid and vapor, anything can get carried over in a distillation when no precautions are taken against it or proper workup is carried out before distillation.

That’s described by the dissociation constant/pKa of the respective acid, which determines acid strength. No dissociation, no H+ floating around.

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Fair enough. Someone mentioned above that this discussion should be framed more in the context of nucleophilicity and electrophilicity, because technically Lewis Acids don’t require the loss of a proton to attract an electron.

Jesus my chem professors would kill me for having regressed this far on reaction chemistry. For shame

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:shushing_face: you’re not supposed to tell anyone about the bigwigs at science

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@TheGratefulPhil, one may consider the hydrogen as remaining practically attached with the molecule. Any disassociation that might occur is instantaneously reversed… and this is exactly the same condition under which acids, bases and other ionic compounds persist, continually, for as long as their atoms exist in that ionically bound relationship. If you consider a covalent bond to be something like two magnets held together by N/S polar attraction, you can think of the ionic bond like a couple of styrofoam packing peanuts held together by static electric cling. In either type of bond, if you separate the atoms a little, they will stick back together when you let go… but while the magnets are hard to keep apart at a short distance, the peanuts probably feel like there is no attraction at all. The same goes for pairing… the magnets moving through a pile will stay with their original partners, while the peanuts may freely switch partners as the pairs jiggle around in the box.

Ionic bonds are ionized, even in the molecule. We just don’t call them “ionized” until the atoms are sufficiently far apart to be considered disassociated. It is this potential between the labile proton (H+) and its conjugate base (b-), even while they are still associated, as they are in a non-polar solution, that gives the acid molecule the ability to act as a catalyst in certain environments, interacting with the energies of the atoms in certain other compounds.

Yes, @tweedledew, you could talk about electronegativity and electropositivity, but both exist in every acid molecule. Therefore, I would just refer to any acid molecules being used catalytically in a non-polar solution as “acid catalyst”. Note: no “-ic” on “acid”. :wink:

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See, my only issue here, is that in the case of free H+ protons, the H itself is a participant in the reaction mechanism and exchanges between molecules—in the case of a Lewis acid not donating a proton itself, you now how to view the mechanism in terms of electronegative influence on the molecules.

So now instead of proposing a mechanism with a clearly defined flow of electrons and protons, I put two molecules next to one another, think about how the Lewis acid effects the bond polarities of each moiety on my molecule of interest and propose a catalytic mechanism.

It hard.

The analogy of the packing peanuts vs magnets is great, but in an anhydrous reaction with no hydronium we’re floating in a sea of magnets—and now we gotta start thinking about orbitals and all kinds of other things that significantly complicate the chemistry.

TL;DR chemistry is hard.

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Well, the H+ from the acid molecule is not necessarily the one that sticks to the carbon… at least not by molecular orbital theory. You are correct that it is complicated, but that’s why I try to simplify things; for myself! I think of that proton on the end of the acid as a naked nucleus at the tip of a magic wand. It stays there, but it pokes the reacting molecule with positivity, instigating the cascading reaction mechanism at the C=C double bond on the tertiary carbon on one side of the CBD molecule or the other. Err… Yeah that explanation got complicated anyway, didn’t it… Sorry, @TheGratefulPhil. :sweat:

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Aaaaaaaaaand that’s what I needed.

From that point, I jump immediately to: what kind of acid to you choose so that the activity of that acid is isolated to that C=C bond?

I know that double bonds exhibit more planarity than single bonds, so it would make sense that the “attack” of the acid is from the “front” or “back” of that specific bond. But what really gets confusing for me, is what’s happening to the electrons in those top THREE carbons of the ring and that methyl group sticking off the top.

What kinda crazy rearrangement is happening up there to shift the bond?

If I were to create an analogy off of yours, the “naked nucleus” imbues that section of the molecule with positivity, one of those protons (in the form of H+) gets booted off and the bonds rearrange?

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https://www.organic-chemistry.org/namedreactions/nazarov-cyclization.shtm

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It’s a bit over my head, but I think it could help

Good questions, @TheGratefulPhil!
First… Probably a correctly “buffered” Lewis acid under thermal conditions at or below room temperature.
Second… I would also reply to @Timmy.d.lux to say please look at this screenshot from my Instagram a few years ago:

Thank you both for stimulating this conversation! :nerd_face:

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