(Mad max's) Recrystallisation and a/b extractions

java · Consumer

This is a good thread to copy and refer to as it is the basic understanding for all your endevours for both new and old chemist's........java

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Recrystallisation and a/b extractions

MaDMAx
(Hive Addict)
03-22-02 12:19
No 286519
LOOK! Recrystallization and A/B general info
(Rated as: excellent) Reply

OK this is for the newbies of now and the future. So when someone asks a
question that is explained with this thread you can tell them they are
remiss in their finding skills and that should have found this thread by
using the fucking search engine (UTFSE). This thread will describe
crystallization of most drugs with an amine such as methedrine (----)
and MDMA.

Definitions

solvent - A substance, usually a liquid, that dissolves something else
solute - A substance that is being dissolved in something else
solubility - How easily a substance dissolves in a certain solvent
acid - A substance that gives up a proton easily
base - A substance that accepts a proton easily
salt - The product from the reaction of an acid and a base
freebase - The natural form of a drug, hasn't been reacted with an acid.
You can change a drug back and forth between the freebase and the salt as
many times as you want.

Explanation of A/B (acid base) extraction

Most drugs have an amine group. This is a -NH2 attached to the molecule
somewhere. NH3 is a base (accepts protons from acids easily) so the drugs
are bases also. Hence the name freebase. When you make the drug, it
usually starts out in the freebase form, which is quite often an oil. What
happens when you react an acid and a base? You get a salt. So when you
take your freebase (base) drug and react it with an acid, you get a salt,
such as a hydrochloride salt if you react it with hydrogen chloride (HCl).

Salts are usually crystalline solids rather than oils or waxy solids,
which is why they are so popular with drugs, it makes them easier to
handle, and the drug properties are not changed. Think about it, you have
HCl in your stomach, and acid throughout your body, so if you ingest a
drug in either form, it will end up being in the same form (probably a
salt) in your body no matter how it started out.

Freebases and salts usually have drastically different properties. An
important one is that freebases are usually soluble (will dissolve in) in
non-polar solvents such as toluene and hot naphtha, and not soluble in
polar solvents such as water. The salts are usually the opposite, soluble
in water, but not toluene etc. This is how acid/base extractions (A/B)
work.

You can basify your molecule with NaOH (lye) to form the freebase, which
is not soluble in water, but it will dissolve in a non polar solvent. So
you add your non-polar solvent and the freebase goes in to it (a lot
faster if you shake it all up instead of waiting for the freebase to float
up to it). Once you have freebase in your non-polar you can wash the
non-polar solvent with water to get rid of any non-freebase drug material
(such as excess lye). The water will not remove any of your freebase.

Then to recover your hydrochloride salt (the most popular form of most
drugs), you react it with hydrochloric acid. Muriatic acid is hydrogen
chloride (HCl) dissolved in water. So if you add this to the non-polar
with the freebase, the freebase will react with the HCl to form the salt,
which is now soluble in water and not in non-polar, so it will dissolve
into the water layer, which you can separate and evaporate to obtain your
crystals.

Since evaporating water sucks, and quite often leaves behind impurities,
it is nice to react your freebase in non-polar with HCl without any water
around. This is when gassing comes into play. You can generate pure HCl
which is a gas without any water, and bubble this gas through your
freebase/non-polar. It will react with your freebase to form the
hydrochloride salt (what you want). Since the salt is not soluble in the
non-polar, it will them fall out of solution as crystals which can be
collected by filtering.

Explanation of recrystallization

Once you have your dry drug hydrochloride salt crystals, sometimes you
want to get them more pure, because impurities can be trapped inside the
tiny clumps of crystals. A good way of doing this is to recrystallize. The
idea behind this is to find a solvent that the crystals are kind of
soluble in and kind of not. Alcohols usually work well for this. When
talking about solvents and solid materials, hot solvent dissolves more
solid than cold solvent, so this can be used to your advantage. (The case
is opposite for gases but I won't go into that).

Get two containers. Put some alcohol in one and bring it up to boiling.
Put your crystals in the other container. Slowly add boiling alcohol to
your crystals and they will dissolve. Use just enough alcohol to dissolve
all of your crystals.

Now since cold alcohol doesn't dissolve crystals very well, cool down the
alcohol/product and the crystals will come back out (recrystallize). The
slower you cool the alcohol, the bigger the crystals are. The bigger the
crystals are, the fewer impurities will be trapped inside of them, and the
purer your product will be. So big crystals = pure crystals (usually).

One good way for ensuring that your alcohol cools down nice and slow is to
put some water in a pot and heat it to boiling and take it off of the
heat. Then put your container with hot alcohol/dissolved crystals in the
pot of water being sure not to get any water into the alcohol, cover the
container, and let it cool down to room temperature. Then you can put the
container with alcohol in the refridgerator to cool more. Then into the
freezer to cool more. Then you can filter your pretty crystals out. Now
there is usually still a little bit of product left in the alcohol, so if
you boil off say 75% of the alcohol and repeat the cooling process you can
get some more crystals.

There are other ways of changing the solubility of the crystals in the
alcohol, such as adding acetone or ether to the alcohol, but the
temperature method works quite well, is cheap, and simple. So newbies
should use it first, then experiment with other methods if they want to.

If you knew all of this already then good for you. If you didn't then I
hope I did a good enough job of describing these two concepts to chemistry
newbies. From now on, if someone asks a question about A/B extractions or
recrystallizations, or a myriad of other questions that can be answered by
this post, tell them they need to learn to UTFSE, then give them a link to
this post.

ballzofsteel
(Hive Bee)
03-22-02 14:44
No 286574
Thankyou Reply

Cheers max,
This will sort the men from the boys.
Good work.

Now iF oNly I couLD read.

paranoid
(Hive Bee)
03-22-02 17:31
No 286650
excellent Reply

This is by far the most clear explanation for an A/B extraction I've ever
read. Well done Max.

Brazilian_Bee
(Stranger)
03-22-02 17:53
No 286657
Good Work Reply

Really loved the way you explained things..Keep up w/ your good work !!

epistemologicide
(Hive Bee)
03-22-02 18:14
No 286667
hailz Reply

worlok taught a myriad of clandenstine maniacs how to cook for a
reason,clear and concise like this step by step very easy on the eye mate
and to obsorb,

alot of people not posting rely on this m8, and you would bee surprised
how much help this is to bees,

thank you

epist.

hatred of ontological wastes, and the marathon!!!!

notfman
(Old Bee)
03-22-02 23:05
No 286747
well done Reply

nice work!

¿Qué te parece? so...waddaya think?

Rhodium
(Chief Bee)
03-22-02 23:20
No 286753
Five star post Reply

This post gets five stars from me.

BenWiFFen
(Line Monitor)
03-23-02 03:54
No 286821
Hot filtering Reply

By heating in iso or methanol and letting evap will just make your gear
better looking. You see that stuff that don't want to desolve? Filter it
out then evap your gear will now bee better.

..Optical Mineralogist in training..

pikkolo_z
(Hive Bee)
03-23-02 09:18
No 286890
great write up Reply

my hat is off to madmax .great write up easy to read and understand . and
good idea makin this a sticky.

you'd worry less what people think of you
if you knew how seldom thay do.

foxy2
(Distinctive Doe)
03-24-02 03:12
No 287282
A/B general info sites Reply

These are good for more info on A/B extractions

http://www.chem.ualberta.ca/~orglabs/separation/Theory/theory4_1.htm
http://www.chem.csus.edu/forkey/Extraction/Forkeys_extraction.html

http://web.centre.edu/~muzyka/organic/lab/24_extraction.htm
http://www.lycaeum.org/drugs.old/other/extraction/extract1.html

Those who give up essential liberties for temporary safety deserve neither
liberty nor safety

aztec
(Newbee)
03-27-02 07:38
No 288545
recryst & a/b info Reply

Thanks MaDMax, I really needed that.

An attorney for free choice, free speech

victory
(Stranger)
03-29-02 14:23
No 289600
liquid to powder Reply

lets say i have liquid k and want to make crystals how would i go about it
? well is their anybody that can tell me how??????????????

MaDMAx
(Hive Addict)
03-29-02 14:51
No 289615
evaporate it Reply

What you have is most likely just ketamine hydrochloride dissolved in
water. So just evaporate the water. I've used a hair dryer, and a small
space heater to evaporate the water from ketamine solutions, but
supposedly it can be done faster with a microwave.

Most pharmaceutical/vet ketamine is dissolved in saline solution, which
means there is a little bit of salt in there. This is why Special K
"cooks" claim to be able to get more than a gram out of their vial. They
have 1 gram of ketamine (you really think pharmaceutical companies are
going to have lax enough quality control to let there be more drug in
there than they claim?), and a little bit of salt to bring the weight up.
This is fine for use because a little salt isn't going to hurt the body,
but, if for some reason you want really pure K, I suppose you could A/B it
to separate it from the salt.

But you will probably be quite satisfied with the product obtained from
simply evaporating the water.

locrian
(Hive Bee)
03-30-02 10:41
No 289919
Reply to 'evaporate it' Reply

True. An A/B is not necessary. Just pour it out on a plate and stick it
in the micro at medium heat for about 3 min. Add more time if necessary.
Works perfectly every time.

We need new drugs.

LaBTop
(Daddy)
03-31-02 01:12
No 290272
A/B not always needed: Reply

Especially when you have distilled MDMA freebase, it is redundant, because
your freebase is already of sufficient purity, and the impurities are left
behind in the heating flask.
A simple gassing in 8x Acetone or DCM (dichloromethane) is producing
sparkling white crystals and for sure after a few washings of the buchner
filtered crystal mass with a small amount of clean cold acetone. LT/

WISDOMwillWIN

locrian
(Hive Bee)
03-31-02 23:55
No 290755
Reply to 'A/B not always needed:' Reply

I've heard MDMA is slightly soluble in DCM and therefore is not
recommended to use with MDMA. I'm sure its fine for MDA, but am I
mistaken here in assuming DCM would not be a good choice for gassing MDMA?

We need new drugs.

LaBTop
(Daddy)
04-01-02 00:51
No 290794
Well, Reply

I assume that cooks work in repeating batches, so the DCM used in the
first batch would be saturated with the max amount of MDMA, thus can be
used again and again to crystallize in the future batches. That answers
your question? LT/

PS: otherwise, just distillate your DCM to recover it as reasonable pure
DCM, and wash the small crop of crystals recovered from it, a few times
with acetone. An ethanol/acetone recrystallization will produce pure MDMA
ofcourse.

WISDOMwillWIN

locrian
(Hive Bee)
04-02-02 00:19
No 291342
Reply to 'Well,' Reply

Good point, yes that answers my question. But, let me ask you this then,
is there any reason why DCM would be preferable to other non-polar
solvents, quantitatively or qualitatively? It has been proposed before
that DCM is the best for crystalization of MDA, producing aesthetically
pleasing crystals that some claim are of higher potency, although
theoretically not really possible. So could using DCM be advantageous?
Also, exactly how much MDMA dissolves into DCM?

We need new drugs.

LaBTop
(Daddy)
04-04-02 21:55
No 292708
Ahumm, Reply

To avoid that nasty UTFetc, search for "Rhodium DCM" in his last posts
since January or later. LT/

WISDOMwillWIN

bujinkan
(Hive Addict)
04-07-02 04:38
No 293633
I Humm. Reply

Nice mad max...about time i say.

kitten
(Stranger)
04-07-02 06:50
No 293677
I am a newbee, this post makes it easy to ... Reply

I am a newbee, this post makes it easy to understand. I would prefer
haveing someone else cook, but I am on my own.
Thanks for the info

nevry
(Stranger)
04-14-02 12:43
No 296877
re: ... Reply

what about alkaloid that aren't basic, such as caffine? What about acidic
alkaloids(or alkaloids that share the traits of both[aka lysergic acid])?
And, does more HN bonds mean better solubility(ie will follow the rules
better)? thanks!

- nevry.

- nevry.

kapen
(Newbee)
04-28-02 13:19
No 302646
umm quick question Reply

>>>>>You can basify your molecule with NaOH (lye) to form the freebase,
which is not soluble in water, but it will dissolve in a non polar
solvent.<<<<<

ok in a couple synths that swik has read, ie.. oxone 2 mdp2p and mm's
benzo and mm's nitro amination.. it states that to make a 5% solution of
naoh you mix the naoh with water to make the solution. being a solution
wouldnt that mean that the substance being diluted is soluable in water.
swik knows this is kind of anul but again swik is confused.
-kap-

Just say know.

Rhodium
(Chief Bee)
04-28-02 13:46
No 302659
clarification Reply

NaOH (lye, sodium hydroxide) is very soluble in water, but amine freebases
usually aren't.

0xYg3n · Wed May 11, 2005 12:30 am

nice explanation.

icecool · Insistent Chemist

Its a very nice explanation really nice to read too and easy to read.
Now I didn't use the FSE good enough to find this so my questions will be deleted in some topics where I asked about how to recrystalize...

loki · guinea pig

i would just like to point out that using a microwave to evaporate alkaloid salts is fine until the solution starts to near saturation and then one can (and frequently does) have problems with superheating causing the precious (and concentrated) alkaloid salts being spread all over the walls of the microwave, on a flat dish, generally only causes splatters but in a taller container a sufficient volume could conceivable go SPLOOSH and blast the shit just about everywhare and leave very little in the beaker. (also superheating can raise temperatures so high that it can cause degradation to some alkaloids)

i personally have found that (i have not used a gassing rig before so i cannot say much about that) for standard titration extraction of freebase in nonpolars into aqueous salts, standardised molarity HCl solution is very helpful, and in fact could allow you to get a fairly good measurement of how much alkaloids you have extracted because you can just titrate titrate (check pH or dip finger and taste so long as alkaloid is not active at microgram levels) titrate and then once it comes out acidic, (be patient, if you want an fairly accurate guage of yield) collect the titrations together, measure their volume, and multiply the molarity of the solution by the fraction of a litre, and then multiply this by the molar weight of the alkaloid and you get the approximate milligrammage (of freebase) that you extracted (add the weight of the acid calculated the same way to it for the weight of salt).

i have found that concentrated acidic solutions (particularly HCl but probably applies equally to any other acid) do not extract alkaloids out of nonpolar containing freebase very well (i may just be impatient, but doesn't seem to happen in 20 minutes even) whereas molar solutions of around 2M or less work much better.

IndoleAmine · Dreamreader Deluxe

Good point - when you use aequous, standardized acid solutions (like 10% of 2M HCl for example), you know how much acid you have in there and can use just a slight molar excess, plus you have lots of SOLVENT present to simplify things... Wink

Also you avoid having locally distributed extreme pH values due to too high H+ concentration, and this is much gentler to your precious molecules (same thing applies for basifying: use dilute solutions of everything!)

Using a microwave for evaporating solutions of salts really is not advised, due to the mentioned problems.

loki · guinea pig

regarding the best strategy for titration, an idea for it occurred to me this evening which would be a good way to get optimal titration with minimal titration passes - calculate how much of your standardised molarity acid solution you expect to need for the total volume, then on each pass, put in half of whatever is left of that volume, and as you progress, each subsequent titration is half as much and when you get to the end of available freebase, more than likely you have got it within a very close margin, because every time you titrate half as much, the closer you get to the expected amount, the shorter the increments.

i personally don't like the idea of gassing whatsoever (when i said i'd not used a rig, i said that in the sense that the one time i tried my rig was a piece of shit and fell apart from the acid pretty damn fast, and leaked HCl gas everywhere...). anhydrous HCl is so evil... but one good thing one learns from gassing is that it's good to dry the nonpolar solvent before starting with the conversion to the acid. Most solvents have at least trace water in them, and that trace water is gonna be your base solution. drying the solvent will pull all the water out that is allowing that stuff to remain in the nonpolar solvent and cause it to deposit with the drying agent, away from the freebase, meaning that the stuff you get out will not have traces of the basifying agent used.

This probably applies even more to when one is ending with the freebase, because the product will then be laced with alkali and as we all know, dry alkali and molted freebase... you couldn't get a much more reactive mixture, in terms of degrading honey (of whichever brand one is discussing)...