Reaction scheme:
Equipment and glassware:
- 5 L Round bottom flask;
- Retort stand and clamp for securing apparatus (optional);
- Reflux condenser;
- Funnel;
- Sieve filter (kitchen grade is ok);
- Syringe or Pasteur pipette;
- pH indicator papers;
- Beakers (500 mL x2, 250 mL x2, 100 mL x2);
- Vacuum source;
- Vacuum distillation apparatus;
- Laboratory scale (0.01-100 g is suitable);
- Measuring cylinders 250 mL, 100 mL and 20 mL;
- Cold water bath;
- Glass rod and spatula;
- Separatory funnel 1 L (optional);
- Buchner flask and funnel;
- Filter paper;
- Freezer;
Reagents:
- Phenyl-2-propanone 40 g;
- Ethanol 200 ml;
- Aqueous methylamine (free base) 200 ml 25%;
- Cut aluminum foil 40 g;
- Mercury chloride (HgCl2) 0.30 g or mercury 2 nitrate (Hg(NO3)2) 0.359 g;
- Distilled water;
- Potassium hydroxide 120 g;
- Diethyl ether (or petroleum ether) 750 ml;
- Magnesium sulphate anhydrous (MgSO4) ~30 g;
- Acetone ~150 mL;
- Concentrated hydrochloric acid (HCl 36%) ~12 mL;
Synthesis:
1. Phenyl-2-propanone 40 g, ethanol 200 ml, aqueous methylamine (free base) 200 ml 25%, cut aluminum foil 40 g and mercury chloride 0.30 g (or mercury 2 nitrate 0.359 g) are placed into a 5 L round bottom flask.
2. A reflux condenser is installed and reaction mixture is refluxed for 2 hours and cooled down to a room temperature.
3. The reaction mixture is poured into a ice-water (1:1 v/v) beaker through a sieve filter (to get rid of solid Al/Hg), flask has to be washed off from residues of reaction mixture to a beaker. The reaction mixture in the beaker is alkalized with potassium hydroxide aq solution (120 g KOH in 250 ml H2O).
4. Then, the solution is extracted with diethyl ether (or petroleum ether) 750 ml.
5. Ether extract with methamphetamine free base is dried over MgSO4. After that, a solvent is evaporated with a slight heating of warm water bath or with help of rotary evaporator with vacuum.
6. Next, crude methamphetamine free base is distilled with vacuum to give pure 1-phenyl-2-methylaminopropane (methamphetamine) with 70% yield.
7. Methamphetamine free base is dissolved in x3 volume of dry acetone.
8. Concentrated hydrochloric acid (HCl 36%) is added dropwise to reach pH 6.
9. The mixture is put into a freezer for 12 hours, methamphetamine is crystalized there.
10. Methamphetamine crystals are vacuum filtered, washed with small amount of cold dry acetone and air dried (or dried in a vacuum chamber).
Related topic
1. Phenyl-2-propanone 40 g, ethanol 200 ml, aqueous methylamine (free base) 200 ml 25%, cut aluminum foil 40 g and mercury chloride 0.30 g (or mercury 2 nitrate 0.359 g) are placed into a 5 L round bottom flask.
2. A reflux condenser is installed and reaction mixture is refluxed for 2 hours and cooled down to a room temperature.
3. The reaction mixture is poured into a ice-water (1:1 v/v) beaker through a sieve filter (to get rid of solid Al/Hg), flask has to be washed off from residues of reaction mixture to a beaker. The reaction mixture in the beaker is alkalized with potassium hydroxide aq solution (120 g KOH in 250 ml H2O).
4. Then, the solution is extracted with diethyl ether (or petroleum ether) 750 ml.
5. Ether extract with methamphetamine free base is dried over MgSO4. After that, a solvent is evaporated with a slight heating of warm water bath or with help of rotary evaporator with vacuum.
6. Next, crude methamphetamine free base is distilled with vacuum to give pure 1-phenyl-2-methylaminopropane (methamphetamine) with 70% yield.
7. Methamphetamine free base is dissolved in x3 volume of dry acetone.
8. Concentrated hydrochloric acid (HCl 36%) is added dropwise to reach pH 6.
9. The mixture is put into a freezer for 12 hours, methamphetamine is crystalized there.
10. Methamphetamine crystals are vacuum filtered, washed with small amount of cold dry acetone and air dried (or dried in a vacuum chamber).
Related topic
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