2CB.HCl synthese

anime · Mon Aug 15, 2005 10:48 pm

well I am certain some of your product is in the DCM since the bromine makes the molecule non-polar. You can first add some Sodium Ascorbate to neutralize the bromine and then basify.

Generally when swim does the reaction he uses HBr which is made from sulfuric acid and sodium bromide, this is distilled to yield a 48% solution (126C). The 2ch freebase is dissolved in GAA, 40% H2O2 is added to the solution and the HBr is then dripped so the temp is maintained at RT, crystals should form very quickly.

Another option is making the bromine and then bubbling it into a GAA solution, and using that.
Also becareful with heating the solution while the is still bromine in solution as you will end up with some dibrominated product.

icecool · Insistent Chemist

Hmm okay, well I eventually heated it to 75*C....
But still before I did that there weren't more or less crystals.
Now the filter is brown and I'll see if there are any crystals on it.
There wasn't any DCM anymore now before filtration since I evaporated it...
So then all the 2C-B.HBr would either dissolve in the GAA or preticipate out.
Next time SWIM won't heat it anymore, and do a bigger reduction.
Since he only started with 5g of nitrostyrene.
And you sayd "The Nitrostyrene is dissolved in GAA, 40% H2O2 is added to the solution and the HBr is then dripped so the temp is maintained at RT, crystals should form very quickly. " Do you really mean nitrostyrene, so you brominate the nitrostyrene or did you ment the 2C-H...
If you DID ment the nitrostyrene you do not need to brominate it anymore afterworths right?
And from the reduction immediatelly 2C-B will form so only HCl needs to be dripped in after worths and you will have 2C-B.HCl ?

icecool · Insistent Chemist

Hmm okay well all the bromine and the product if it's there all went into the DCM.
Haven't got sodium ascorbate...or I would have to go and crush some vitamin pills.
But well now I got a dark red DCM layer.
There was nothing on the filter, or at least not anything which could be recovered.

EDIT:
Just had a "genious" idea, why not just a/b it...
SWIM added DCM so the bromine went in there and the freebase went in there.
So still not what SWIM wanted, so he added H2SO4 to it until acidic, then got rid of the DCM and washed with more DCM and then added NaOH solution until white cloudiness persists, and now added DCM and adding more NaOH until pH >14 and then evaporating the DCM and adding IPA and then adding HCl.
But first SWIM has to go further with making the pH >14.

anime · Tue Aug 16, 2005 1:50 am

my bad, I meant the freebase amine.

What you might try doing is bromination of the benzaldehyde before condensation with nitromethane. That way after the rxn you don't have to bother with bromination. The DCM method works very well when doing this and the Al/Hg does not do any dehalogenations.

Make sure you crystallize your nitrostyrene and utlimately it would be ideal to distill the 2c-h before bromination but when working with small amounts it is impractical.

icecool · Insistent Chemist

I did crystalize the nitrostyrene, and ow before I forget I'm quite sure SWIM made himself some 2C-B.HCl !!!!!
Anyway this is how it went.
anime told me to add DCM, now bromine and the freebase went into the DCM.
I wanted to get rid of the DCM so I added acid to the mixture, now the bromine remained in the DCM and the freebase became the sulfate in water solution.
Now SWIM washed 3 times with 5ml DCM...last wash was almost clear and not red/yellow anymore.
Now SWIM added NaOH solution to pH >14 first there was the white stuff again (emulsion of freebase and water).
Anyway when the white stuff persistet DCM was added and more NaOH was added...
Then the DCM was washed with water and brine 3x.
Now the DCM was evaporated for a bit because it took so long SWIM added a few drops of GAA and few drops of water and then shook very hard to get the 2C-B.Ac then added a few drops of HCl 30% and there were some white crystals which disapeared as quickly as they came so SWIM added some more drops like 4 in total or so.
And then put the beaker with water in the freezer, now a couple of hours later the water froze and there are like 15 crystals (not needles but more like little balls or cubics) are in the bottom captured in the ice.
Tomorrow SWIM will throw the chunk of ice in the buchner and set it on vacuum filtration so as soon as some water melts it gets sucked away so it can't dissolve the precious crystals.
Ow and the NaOH+freebase at the last a/b purification smelled a bit fish like ( so that's a good sign).
After all this shitting around SWIM luckely did get some crystals so next time he'll do an 10g nitrostyrene reduction and then see if he can do it better with the bigger amount since that's more easy (no time for arguments now too tired).
He has now done the reaction so everything will ofcourse go a lot smoother.
And the bromination works like a charm Smile

all credit goes to nicodem! Thanks man!
SWIM is wondering if he could have made ANYTHING else out of this crap which forms an oil and makes an not soluable hydrochloride salt :p
SWIM guesses it can't be much more other things then 2C-B.HCl
Maybe 2C-B.HCl which has also been brominated on the 6th position as well as on the 4th but well that doesn't matter that much Very Happy

Ionium · Tue Aug 16, 2005 3:45 pm

To make the HCl-salt, I would think the easiest would be to simply make the HBr-salt first, purify it by rxtl, and then simply dissolve it in dH2O and add HCl in an equimolar amount. I would expect the 2C-B.HCl to precipitate the moment HCl is added due to it's insolubility in water. To avoid encapsulating water inside large chunks of crystal, perhaps it'd be best to add it dropwise and diluted to 5-10%.

icecool · Insistent Chemist

Well since SWIM didn't get any 2C-B.HBr crystals SWIM couldn't recrystalize them etc.
So SWIM just basified the complete mixture and did an a/b extraction and now SWIM does have 2C-B.HCl crystals in ice...

Radiumhero · Thu Aug 18, 2005 11:09 pm

next time u try that synth use elemental Br2 ( works much better event its a payn in the ass to store it in the house , believe me got this stingy ordor still in my nose , ahh and dont forget it fcken eats through plastic ...) i think there is stuff in the dcm extract u better keep out of the synth ...
Since Swirh watches a nice 25 g btch o 2. 5 dimethoxybenzaldehyd lighten up on his cupboard he should try som DOB since the comeout even less than 50 mg
can provide some nice trips since the dose is around 2-3 mg dependin on weight

icecool · Insistent Chemist

Do you mean when extracting the bromine out of KBr and H2O and H2SO4 and H2O2 that also other crap goes into the DCM?
How can you get pure bromine with this same reaction?
Will it just go float underneath the water layer, so I can drain it in a seperatory funnel?

Radiumhero · Thu Aug 18, 2005 11:31 pm

some of the bromine made by this reaction will eventually go into solution since of the rather big vdw powers , u should be abled to obtain rather pure Br2 by overheating ur Kbr and destill the bromin ( takes time an effort )

anime · Thu Aug 18, 2005 11:47 pm

Making bromine.

In a 2-neck 500ml flask add your kbr, h2so4. Then drip your h2o2 to that solution using stirring. the flask should heat up as bromine is being generated. Connect a hose to the flask, take the house and place it in a GAA solution that you have weighed out. After the addition of all the h2o2 heat the solution on a steam bath to 40-50C and the bromine should come over and bubble into the GAA solution where it dissolves.
Thoughout this becareful of suckback.

Once you are done, weight your GAA solution to determine bromine content. At this point the solution is a orangeish red.

You can use this solution for bromination. I haven't included any amounts because I'm lazy but you get the general proceedure.

icecool · Insistent Chemist

Would it really make that much of difference compared to the method of DCM+the whole mixture?
Since nicodeum uses it and several others and they love it...

Radiumhero · Fri Aug 19, 2005 3:09 am

dont know if it is really more diff , just put it in your dest ap.
give it a good heat and the cryst gtr will break down and ll free the bromine ( works with iodine too ) now just cool and get good ventilation ( do it outside unless ur stuff is really gass-proof )

anime · Fri Aug 19, 2005 5:48 am

Really there shouldn't be much different. I find it much nicer to work with than using the DCM method. (Once you have the bromine in GAA). It is a little more work.

icecool · Insistent Chemist

Can it be done in a rotavap?
And do you need to apply vacuum, or would that fuck up SWIM's vacuumpump?
SWIM has got an fumehood so that shouldn't bee a problem.