Need pointers on ways to purify a pyrrolidinophenone (a-PiHP analogue)

[MethylAminoNH3]

Hello,
New member here, but been reading for atleast 5 months.

I have basic chemistry knowledge and a little more. I have studied "Chemistry 1" its called in my country. Its Chemistry for highschool (Age ~15). I have also read about Organic chemistry and Pharma-chemistry for about 3 years by reading books and online. And im about to apply for to study Organic Chemistry in the university.

So, to the question.

I LOVE Pyrrolidinophenones like a-PVP, a-PHP and so on. My favorite is a-PiHP and a scandinavian exclusive 2-methyl-PVP. This scandinavian vendor has now released 2-methyl-PiHP (2-methyl-alpha-PiHP)
IUPAC for 2-Me-PiHP is below
1-(tolu-1-yl)-4-methyl-2-(pyrrolidin-1-yl)pentan-1-one (So just like a-PiHP but with an added methyl group at the 2nd carbon on the aromatic phenyl ring.)

Its pretty weak regarding potency. And it seems like they are having issues with the purity. The first batch was awesome. A homogenous, white crystalline powder. But the latest month the batch has been light-yellow and the potency as decreased ALOT.

Normally, I would recrystallize it with either distilled H2O or pure Ethanol. But my condenser on my distillation setup is cracked and useless.

Is there any other way to purify it?

Chemicals I have at my hand is Hydrochloric acid 30%, anhydrous acetone and bleach that contains Sodium hypochlorite. (I doubt the bleach can purify tho as it is a oxidizer)

Any tips?

 

[HerrHaber]

If it is supposed to be a hydrochloride (just guessing) recrystalisation from water is the best way to go you can add some ethanol to the water prior tho recrystalisation to slightly decrease solubility at room temperature (several hours in the freezer is also advised) after filtering the precipitate you can add some cold acetone to the filtrate (the liquid) and it may precipitate some more upon further cooling. Bleach and acid are sure to ruin your material so please don't. The decrease in potency compared to the 4 methyl is due to the fact that the additional methyl on the 2 position on the aromatic ring slightly hinders the docking of the molecule in the target protein (receptor or/and transporter). I hope this is helpful and don't forget to read or watch an explanatory video on recrystalisation.

 

[MethylAminoNH3]

To above: Im sorry, i havent read yet. I wll do now, but i wanted to show pic first.
Here is a picture

I dont have distilled water. My condenser is cracked... And tapwater contains so much else and it makes the crystals taste like shit..
Buut... The actual coil where the vapor goes thru is not cracked.. I could cool the coil in the condenser with a freezed cloth..
The ethanol contains many other things as i said.. It isnt distilled cuz my condenser is broken.

I have done recrystallization ALOOOT. With distilled H2O and always have VERY good results. But i dont have a distiller so i cant distill my tapwater.

O i forgot to mention. The ethanol i have now isnt distilled.
It contains Ethanol, Propan-2-ol and denatonium benzoate. Propan-2-ol is Isopropylaclhohl, right?
Wouldnt t the denatonium benzoate ruin everything? Taste wise

 

[HerrHaber]

As far as 4 years of PhD in preparative organic chemistry I only used distilled water when I had a certain reason to believe ions present would be problematic, so I've done countless syntheses and recryustalizations from tap water but I can give you a good tip: buy carbon tablets from the pharmacy, crush them and add to boiling water then filter it (I also know that distilled water should be cheaper and more easy to get at any supermarket or gas station or whatever). A condenser is not normally used for recrystalizartion especially from water, just old fashoned beaker of appropriate size (thank you Berzelius), a bigger round bottom flask full of cold water placed on top is a reasonable condenser if you use a mixture of water and some miscible solvent, in your situation a bit of acetone since is the one you have pure. DO NOT UNDER ANY CIRCUMSTANCE USE DENANTONIUM BEZOATE SPIKED ALCOHOL!!! it's the bitterest substance known and it will totally spoil your stuff. God luck and good speed!

 

[MethylAminoNH3]

Hehe, yes I know Denatonium B is the most bitterest substance. I just stated what I had. And I know a condenser isnt used in a recrystallization. But I need to distill my tapwater to do a Re-X. I did a Re-X with tapwater before, and it made it vaporize worse, it tasted worse due to the minerals and shit.

And water + acetone forms a azeotrope... I wouldnt use H2O and Acetone to Re-X.

 

[MethylAminoNH3]

Cant I turn my PV to the free base, extract the freebase oil or extract the water and leave the freebase oil in the vessel.
Wash it with suitable solvent (Maybe I can skip this? |Question: When made to the freebase oil, is it more pure than the starting HCl powder?)

And then turn it to HCl again using Hydrochloric acid 30%.

 

[MethylAminoNH3]

It is soluble in acetone. But maybe some impurities isnt? Should i dissolve it in acetone and then get rid of the insolubles, and then let the acetone solution containing my substance to evaporate? Would that clean it up a little?

 

[HerrHaber]

I would stick to water and maybe 10 to 15% acetone to decrease solubility at cold, you can filter twice first at room (or outdoor) temperature and then add some more acetone to the filtrate and put in the freezer for couple of hours then filter while cold (tip: place the funnel in the freezer with the container of filtrate) the difference in the solids (if there is one) may be relevant to you... I know what to expect but I will let you learn from experimental discovery since is more educative from me )
P.S. you do have a point and what you said isn't completely wrong but it may not be as rellevant as you think.

 

[MethylAminoNH3]

as said.. Tapwater has minerals and will ruin the taste and vape experience. And the solubility in H2O is already very low, like 10mg/ml (25c). I've done countless of re-X with these Pyrovalerone analogues. But only with distilled H2O

 

[HerrHaber]

The rellevant solubility is in the near boiling water since re-x is dissolving the solid in boiling solvent then set aside wrapped in alu foil and a towel undisturbed so that it comes back to room temp as slow as possible then put in freezer to increase yield. Since you plan on vaping it I doubt 100C will harm your stuff but be minful of the fact that you need to saturate boiling water with the solid so don't just make a solution that you need to evaporate in order to recover the best.

 

[MethylAminoNH3]

As stated, I know how to do a single solvent recrystallization. I have done over 100x of them, mainly with distilled H2O. I oversaturate the solution with the substance at around 90-96 celsius. And I then let the solution cool to RT very slowly in a water bath that is around 40c.
Once it reach RT, I cool it to around 15c. Then I put it in the refrigerator for 20min. And then I put it in a ice bath until the mother liquor reaches around 2-3c.

I then filter it thru a vacuumfilter and rinse with ICE-COLD dH2O.

I know how to do a re-x.

My question here was how I can purify with the solvents I have at hand.
Especially by turning it to freebase, dissolve the freebase in example Chloroform (If that can dissolve the freebase ofc). And then make it to HCl again.

My ethanol isnt ready. Its "Red Ethanol". Maybe called Bio-ethanol" in USA. Its Ethanol, IPA, MEK and Denatonium Benzoate.
I tried adding some bleach (Sodium hypochlorite) to a test tube containing my red ethanol.

The color shifted from red to completely clear, like water... Did that remove the denatonium benzoate?

 

[HerrHaber]

Excuee me again for misjudging your competence, you are again right if you wish to freebase the stuff use aqueous NaOH (easy and cheap sold as drain cleaner... in Europe I suggest MrPropper the one sold in an orange box that contains a plastic jar it is pure NaOH granules since even if you find little bags some may have colouring and perfume... no no, the one I mention costs the equivalent of 2,5 euros or so) then extract with chloroform (liver damage and drowsyness spoiler alert) carefully acidify with dry HCl gas since is best but 30% can work well stirred and then again frozen before vac filtration then wash with acetone and dry under vacuum. Your ethanol is only discolored by the bleach and is even worse now, denantonium benzoate may be partially hydrolized but believe me it is hell bitter and it still does pose a serious threat to your material... you need a condenser after all, you can only distill the ethanol to make sure and it won't be very pure anyway but other solvents are not that much of a problem. In order to eliminate both color and bitter stuf from your alcohol the activated charcoal can be used (also found in pharmacy as tablets) even opening a fresh gas mask cartridge has the same. Had I not have my lab taken away from me by some idiot you would have had a nice condenser sent over from me as a gift.

 

[m924]

Don't have much knowledge myself but i think that some RE-Xs should work well, besides that I don't have much to say sorry!