Methamphetamine after resolution, recrystallization problem
- Thread starter @wangxiaolin777
- Start date
1. Dichloromethane has low solubility to methyl hydrochloride and cannot be completely dissolved.
2 The boiling point of dichloromethane is relatively low, and the evaporation is too fast to form large crystals, and will only appear as crystalline powders.
3. Clean the hydrochloride before recrystallization, (acetone, ether, dry and cold)
4. It is recommended to use - acetone: water, acetone: ethanol, acetone: methanol, ethanol: water, methanol: water, for recrystallization.
Water can slow down evaporation, acetone can reduce solubility, and alcohol can form better crystals.
2 The boiling point of dichloromethane is relatively low, and the evaporation is too fast to form large crystals, and will only appear as crystalline powders.
3. Clean the hydrochloride before recrystallization, (acetone, ether, dry and cold)
4. It is recommended to use - acetone: water, acetone: ethanol, acetone: methanol, ethanol: water, methanol: water, for recrystallization.
Water can slow down evaporation, acetone can reduce solubility, and alcohol can form better crystals.
Teacher, my hydrochloride is clean. I extracted it by petroleum ether and breathed it into hydrogen chloride gas, then dried it. Is pure ethanol OK? Or can you tell us the procedure
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- By Bmth
Once done with the Synthesis of I2 & Red Phosphorus, Do we have to go this route https://bbgate.com/threads/methamphetamine-isomers-separation-by-tartaric-acid.9690/
Then the crystallisation process?
Then the crystallisation process?
- By Acab1312
If you have the d-isomer (by separation with tartaric acid or by synthesis with ephedrine).
I can highly advise for the method I read with a member.
40 g D-meth
100 ml acetone
9.5 ml h20
-Mix everything heat to 55°
-Let cool at room temperature for 3h
- in refrigerator for 2h
- Freezer for 2h
Very easy, very fast, thanks to the member who shared it. Unfortunately, I don't remember the name.
I can highly advise for the method I read with a member.
40 g D-meth
100 ml acetone
9.5 ml h20
-Mix everything heat to 55°
-Let cool at room temperature for 3h
- in refrigerator for 2h
- Freezer for 2h
Very easy, very fast, thanks to the member who shared it. Unfortunately, I don't remember the name.
Because you didn't do it correctly. You just add the solvent and then evaporated that. It's not a recrystallization procedure, which is known as purification method.