- Language
- 🇬🇧
- Joined
- Jan 1, 2023
- Messages
- 64
- Reaction score
- 76
- Points
- 18
Introduction:In the following, forum members will be presented with a synthesis that is very easy to perform, does not take much time, and gives an exceptionally high yield. The method is a result of many years of experience and inputs from various sources that go back to the times of the legendary Hive forum. All of them deserve high recognition and a great tribute is paid to them.
Reaction:
Reagents:
1. 2-bromo-4'-methylpropiophenone (CAS 1451-82-7) 500 g;
2. Methylamine 40% aq – 750ml;
3. Hydrochloric acid (HCl 37%) appr. 250 ml;
4. Distilled water, clean tap water;
5. Dichloromethane 2,3l;
6. Tetrahydrofurane, (Aceton);
Procedure:1.Dichloromethane (DCM) 1.5 l is poured into the reactor/flask and a condenser is attached.
2. 2-bromo-4'-methylpropiophenone 500 g (CAS 1451-82-7) is added.
3. The mixture is stirred until complete amount of bromoketone is dissolved.
4. Methylamine 40% aq, 750ml is added slowly with a drip funnel.
6. The mixture is stirred for 2 ½ h at 38 °C. .
7 After that, the reaction is quenched by adding 7000ml ice cold clean tap water.
8. The mixture is stirred for 1-2 min and the DCM layer is separated off.
9. The remaining freebase is extracted with 500 ml DCM.
10. The combined organic layers where washed twice with 300ml water.
11. The combined washed organic layers were acidified with 2 M hydrochloric acid (37% hydrochloric acid is diluted 1:5 with water) to reach pH5.5-6 with constant stirring.
12. The acidic extract was washed with 300 ml DCM and the water evaporated under vacuum (e.g. in a rotovap) until a viscous liquid is formed.
13. After that, the mixture is poured into a buchner funnel and carefully filtered. At first only with gravity, then vacuum is applied until an off white solid is obtained.
14. The crude mephedrone hydrochloride is rinsed thoroughly with cold THF (acetone if THF is not available)
15. The washed product is put into a Pyrex dish, or similar and dried to constant weight.
Yield 310,57g or 79,59% of theory.Attachments
Last edited: