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Cocaine water dissociation

M

melarsoprol

Bluelighter
Joined
Feb 27, 2007
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186
First of all, I dont know if this plausible for ADD, but im interested in the science aspect of my question.

Cocaine hcl is a salt, which means in water, it dissociates, binding on to the H and O molecules of water.
In the simple example of NaCl, Na binds to O and Cl binds to H. How does C17H21NO4 (cocaine hcl} dissociate and bind in water? Whats the split?

Another question I had was. If SWIM was to dissolve 5 g of cocaine hcl {assuming its pure} into pure distilled water, how much cocaine will i lose by evaporating the water out? Basically, how much would i yield from my original 5g if I changed the state of cocaine hcl from solid, liquid, back to solid?

By the rules of chemistry, I should expect a microscopic loss of product, but how significant would the loss be?
 
The description of Na and Cl "binding to" parts of water is a bit of a misrepresentation.

When an ionic substance is dissolved, it will dissociate*. In the case of NaCl, you get Na+ and Cl- ions in the solution**. While, yes, indeed, the oxygens on the water molecules are attracted to the Na+'s (because the oxygen has a partial negative charge), and the Cl- to the hydrogens, these intermolecular forces do not constitute a bond.

In the case of Cocaine HCl (C17H22NO4Cl) (the formula you gave was for the free base), you get Cl- ions and C17H22NO4+ ions (with the extra hydrogen and a positive charge on the nitrogen). Same goes for other alkaloids.

On to the practical question:

There is no issue with cocaine being lost by dissolving it in water and allowing the water to evaporate, you'll just once more be left with cocaine HCl. Cocaine (as with almost any other alkaloid drug) is not volatile at room temperature as the HCl salt, in solution or otherwise, and it is also quite stable, so there is no loss from chemical reactions to be expected. Your only loss would be, as they say in chemistry, "mechanical losses", ie, stuff that gets wasted because you don't get the last drop out of a container or something.


*Not everything dissociates completely. weak acids and bases do not (ex: vinegar or citric acid - except in dilute solution, most of it is not dissociated).
** This means that if you dissolve 1 mole of NaCl and 1 mole of KBr in water, it's indistinguishable from a solution made from 1 mole of NaBr and 1 mole of KCl
 
Thanks for the quick reply.

So cocaine is quite stable, whether its in a solid or aqueous form. Then, even prolonged dissociated form of cocaine {Cl- ions and C17H22NO4+ ions} should remain stable.

Cocaine hcl's melting point is relatively high at 197C, however, would changing its form to aqueous change the melting point? So lets say i wanted to speed up the evaporation of water by heating it under a flame or an oven. Would this jepordize the quality of cocaine hcl in anyway?

If it does, what about anhydrous isopropyl alcohol or other liquids with a lower boiling point and tolerance to cocaine dissociation?
 
What you would have to worry about it the high temperature enouraging degradation of the cocaine.

I think if you use gentle heat (not boiling it or anything) you'll be fine though. Cocaine doesn't have a reputation for degradation.

What, may i ask, are you attempting to do?
 
Nothing too complicated. Just wanted to store some yayo long term in liquid to avoid suspicion for I will have to leave the country for a little bit.
 
aaaah, if you're storing it long term, you need to be worried about bacterial/fungal growth. I'd throw some alcohol (rubbing alcohol or vodka) into it and be sure to use distilled water, to prevent shit from growing in it.
 
hm, then what about just dissolving the whole thing into anhydrous isopropyl alcohol or some kidna solvent?

What do you suggest? Id go for some other hydrocarbon structure with a lower boiling point to minimize the evaporation time, but also some with anti-microbial properties such as alcohol
 
I'd just stick with rubbing alcohol or grain alcohol. We don't need to get fancy here, and unless you're dissolving it in a huge amount of liquid, it's not going to take _that_ long to evaporate whatever you're dissolving it in.
 
If you were me, and you had to get fancy, with a lot of liquid, money and effort what would you do?
 
Could you expand on it a little bit?

when you say ester function, does cocaine hcl contain an ester function?
From my knowledge, an ester is a combination of an acid and alcohol.
And when you say long term, is there a general time period? or would it be more of a "the longer it stays aqueous, the more conversion, hence loss of cocainehcl"

moreover, can hydrolysis occur with water? this may seem like a silly idea but can hydrolysis occur with other solvents that liberate H+ molecules? If not, arent many hydrolytic reactions reversible?
 
Cocaine has two esters, hydrolysis could definitely be a problem.

I hadn't thought of that (I don't touch coke).
 
Okay so ive confirmed that hydrolysis CANNOT occur without water, despite other proton {H+} liberating compound such as acids.

so would adding alcohol take care of both, anti-microbial and hydrolytic problems?
 
Alcohol could cause transesterification... which won't destroy the drug, it just turns it to cocaethylene:

Cocaethylene produces a more euphoric stimulation than cocaine in most users, and is longer lasting in the body. Some studies suggest that it may have a higher cardiovascular toxicity than cocaine. Cocaethylene however is less potent at binding to serotonin and norepinephrine transporters than cocaine is.
Click to expand...
 
Cocaine HCl is sold as 4% and 10% topical solution. I looked up the MSDS on one of these and (as far as handling instructions) it only said to keep it away from silver nitrate and some other things. I'm guessing if you seal it right and store it at room temperature, 1 gram will keep well in 10 mL of sol'n. Just find out which solution compounding pharmacists use.

MSDS said appearance was a greenish transparent liquid.
 
seep said:
Cocaine HCl is sold as 4% and 10% topical solution. I looked up the MSDS on one of these and (as far as handling instructions) it only said to keep it away from silver nitrate and some other things. I'm guessing if you seal it right and store it at room temperature, 1 gram will keep well in 10 mL of sol'n. Just find out which solution compounding pharmacists use.

MSDS said appearance was a greenish transparent liquid.
Click to expand...

This seems to contradict the claim of cocaine degrading during storage in water (which surprised me, but i deferred because i don't know much about coke). Since it's sold as a solution, i'd research the properties medical preparations of it (does it have a short shelf life?)
 
A couple things. feel free to correct me anywhere

Activation energy may be key, and putting the hypothetical cocaine + water/alcohol family solvents may slow down the process of cocaethylene conversion, IF conversions are to take place

Brilliant idea with the MSDS. I looked, and they had a 99.9% methanol and .1% cocaine hcl solution. It states that it is stable when kept at temperatures to 6-8C.
Moreover, it says to avoid acids, acid chlorides, blah blah blah.

So is this the answer to my question? pure anhydrous methanol?
 
Um, their product description has 4-10% splack in water, citric acid and sodium benzoate.

Roxane

Inactive ingredients are in alphabetical order! Bottom line says store at room temp.

They used to make coca wine without having the molecule torn apart in solution. Maybe look up some old recipes.

Oxygen is your enemy.
 
hm im not sure as to what youve posted because i cant open it. however, is this not plausible?


Product Name COCAINE HYDROCHLORIDE METHANOL SOLUTION
Product Number C1528
Brand SIGMA

Company Sigma-Aldrich

Substance Name CAS # SARA 313
COCAINE HYDROCHLORIDE SOLUTION, None Yes
1.0 MG BASE/1 ML IN METHANOL

Ingredient Name CAS # Percent SARA 313
METHANOL 67-56-1 99.9 Yes
COCAINE HYDROCHLORIDE 53-21-4 0.1 No

STORAGE
Suitable: Keep tightly closed. Keep away from heat, sparks, and
open flame.
Store at 2-8°C
STABILITY
Stable: Stable.
Materials to Avoid: Acids, Acid chlorides, Acid anhydrides,
Oxidizing agents, Alkali metals, Reducing agents.
 
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