Starting Reagents and Materials
- 6 g Synthetic ephedrine hydrochloride racemic
- 12 g I2
- 10.8 ml H3PO2 (50%)
- 20 ml H2O
- 50 ml 25% NaOH (15-20 г NaOH)
- 3 g sodium thiosulfate
- 250-300 ml DCM
- 30-50 g Na2SO4
- 100 ml Petroleum ether
- HCl gas
- 100 g NH4Cl
- 25 ml H2SO4 83%
- Flasks 250 and 500 ml
- Glasses
- Funnels
- Separating funnel
- Magnetic stirrer with heating
- Flask heater
- Reflux
- Paper filters
- Pipettes
- Porcelain filter for vacuum filtration
- Chen's reagents
- Simon's reagents
- pH indicator paper
The process way presented on Scheme 1.
Starting reagents for meth synthesis: synthetic ephedrine hydrochloride, I2 and H3PO2. Fig. 1
Ephedrine hydrochloride ground into a powder in a mortar. Fig 2
The powder of Ephedrine hydrochloride is poured into the flask. Fig 3I2 is ground into a powder. Fig 4
The powder of I2 is to the Ephedrine hydrochloride in the flask and continuously mixing. Fig 5The H3PO2 is added in portions to the mixture in the flask while continuously mixing. Fig 6
The reaction is very intense. Reflux connected to the flask. Fig 7
The following portions of acid are added after the cessation of the vigorous reaction. Fig 8
The mixture is heated at a temperature of 100-160°C for 10-12 hours. Fig 9
The solution should become transparent and homogeneous. Fig 10
To the resulting reaction mixture, 15-20 ml of water is added. Fig 11
NaOH solution is added to the RM until reaching an alkaline pH. Fig 12
Next, sodium thiosulfate solution is added. Fig 13
The mixture cooled and added 100 ml of DCM (boiling point of DCM is 40°C). Fig 14
The mixture is transferred to a separating funnel. DCM is separated. Additionally, 2-3 extractions of DCM are carried out with portions of 40-50 ml each. Fig 15
The layer of DCM is dried with sodium sulfate. Fig 16
The DCM is distilled at a temperature of 90-110°C until the distillation of DCM ceases. Additionally, sodium sulfate is washed with new portions of DCM. Fig 17
To the obtained oil, 30+30 ml of petroleum ether is added. Fig 18
The solution is filtered through a paper filter. Fig 19
Impurities is in the distillation flask and on the filter. Fig 20
Solution of methamphetamine in petroleum ether is saturated with gaseous hydrogen chloride until reaching an acidic pH. Hydrogen chloride is generated by adding sulfuric acid to ammonium chloride. Fig 21
The precipitated meth hydrochloride is filtered. Fig 22
Simon's reaction with meth hydrochloride is positive (blue coloring); Chen's reaction is negative; Chen's control on a clean sample of ephedrine is positive. Fig 23
The filtered meth hydrochloride precipitate is dried on the air. Fig 24
Yield is 4.24 g or 77.1 %
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