Author Topic: Wrong A/B extraction of ephedrine?  (Read 3691 times)

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place

  • Guest
Wrong A/B extraction of ephedrine?
« on: March 04, 2004, 11:30:00 AM »
SWIM made a A/B extraction of some powder ephedra 8% plant, using chloroform.

After evap the water, SWIM got brown powder. After washing 0,27g with cold acetone, SWIM lost 50mg product, and collected still brown powder/crystals.

Is the product pure enough to use in rP/I2 reaction?

Why doesn't there appear pure white crystals?


Newton

  • Guest
An A/B of Ma Huang powdered extract is ...
« Reply #1 on: March 04, 2004, 11:51:00 AM »
An A/B of Ma Huang powdered extract is generally considered to be impossible, at least at acceptable yield.

Give some more info on what you did exactly. How much Ephedra was used? How much base addes? Amount of solvents?

place

  • Guest
Well, the extraction was pretty sloppy made...
« Reply #2 on: March 05, 2004, 12:11:00 PM »
Well, the extraction was pretty sloppy made (the last extraction was made with tapwater, SWIM ran out of dH2O). SWIM had first tried a steam extraction, but fucked it up. So instead for that the ephedra-shit go straight to the dump, he lightly boiled the water + plant in dH2O, pH 1. Afterwards SWIM pH 14 the water and extracted the E with chloroform and again dH2O, pH 1.

After evap the water, SWIM got about 3-5g of brown crystals.. And 250g ephedra 8% was used (talking about bad yield.. hehe.. 

SWIM doesn’t give a fuck about losing the plant material; he just did the A/B instead for throwing the plant shit away.

The reason why SWIM asking, is because of he is not sure if the brown/white crystals really are E? But can it be anything else?


thefips

  • Guest
Why do you think the extraction is impossible?
« Reply #3 on: March 07, 2004, 06:19:00 AM »
Why do you think the extraction is impossible?The yield is not so good,but getting white needles of freebase or the hydrochloride is not too difficult.
First extract the 8% Ma Huang with MeOH,a soxhlet wohld be fine,but you can also boil it two times with MeOH.Then evaporate the MeOH to get a brown paste.Then acidify it with dilute HCl and extract 3 or 4 times with ether,EtOAc or toluene.The organic solvent gets brown,in the second extract it gets yellow and in the 4th extract it gets relatively colourless.Then basify the solution by adding K2CO3 and extract 3 or 4 times with ether,EtOAc or toluene to get the ephedrine-freebase.If you destill off most of the solvent and put the flask into the freezer for a while you get white needles of freebase.Then you just have to make the salt by adding H2SO4,H3PO4 or HCl(g).

You first extracted the freebase in plant material with the oily substances of the plant.then you removed the freebase by washing it with the acetone,besause the freebase is soluable in acetone,if you do not acidify it first.

Newton

  • Guest
Why do you think the extraction is impossible?
« Reply #4 on: March 07, 2004, 09:31:00 AM »
Why do you think the extraction is impossible?The yield is not so good,but getting white needles of freebase or the hydrochloride is not too difficult.

That's what I said, impossible at acceptable yields. Plus, I was talking about a straight A/B extraction of the powder, which is called 'Ma Huang 8% extract', because the manufacturer  increased the alkaloid content by extraction, and following addition of the extract to unprocessed plant matter.

Processing a methanol extract is a different matter. This will get you some clean alkaloids, but you need a soxhlet, or go through the hassle of doing multiple boils and washes with a volatile, toxic and flammable solvent.

You first extracted the freebase in plant material with the oily substances of the plant.then you removed the freebase by washing it with the acetone,besause the freebase is soluable in acetone,if you do not acidify it first.

The ephedra salts were reclaimed from the chloroform with acidified H2O, from what he wrote.

place

  • Guest
The brown crystals WAS ephedrine.
« Reply #5 on: March 07, 2004, 09:55:00 AM »
The brown crystals WAS ephedrine.

But still, the yield are really small.


thefips

  • Guest
Sorry,I thought you extracted the basic ...
« Reply #6 on: March 09, 2004, 08:42:00 AM »
Sorry,I thought you extracted the basic solution with acetone.But normally the crystals become white or light yellow by washing them with acetone.
The yields I had were ~30-35%,but I only hab little material to extract.
But I think if there is another source für ephedrine the extraction from the 8% Ma Huang is too much work.

place

  • Guest
But the plant ephedra is a LOT cheaper!!
« Reply #7 on: March 09, 2004, 10:08:00 AM »
But the plant ephedra is a LOT cheaper!!


Newton

  • Guest
I thought you extracted the basic solution...
« Reply #8 on: March 09, 2004, 06:27:00 PM »
I thought you extracted the basic solution with acetone

And how would you proceed doing that? Water and acetone are completely miscible.

thefips

  • Guest
Soory,again it was the wrong word...
« Reply #9 on: March 11, 2004, 03:54:00 PM »
Soory,again it was the wrong word... My english is horrible.
I wanted to say that I thought he extracted the solid ephedrine freebase with acetone.