10. Methamphetamine crystals are vacuum filtered, washed with small amount of cold dry acetone and air dried (or dried in a vacuum chamber).
Can I make Methylamine in situ. via nitromethane like they do when reducing MDP2P
can i replace the methylating agent with formaldehyde?
formaldehyde and primary amine gives the corresponding imine, which even though can be reduced by NaBH4, STAB (Na(OAc)3 aka sodium triacetoxy borohydride is much preffered since it has a strong prefference for reducing imines, also NaBH3CN id used for this purpose but somewhat toxic and expensive
can i replace the methylating agent with formaldehyde?
can i replace the methylating agent with formaldehyde?
6. Next, crude methamphetamine free base is distilled with vacuum to give pure 1-phenyl-2-methylaminopropane (methamphetamine) with 70% yield.
(step 6.) What should be the range of temperature of vacuum destilation (to effectively get rid of impurities, and avoid freebase decomposition)?
Right question to ask but the answer is in the relationship between the strength of vacuum and temperature (the more negative the pressure the lower the boiling point) I suggest not playing arround with super strong vacuum if you have no experience before hand. God luck and good speed!
Thank you for your answer. Is there any critical, upper temperature limit? (or maybe proper question will be - what is decomposition temperature of methamphetamine freebase?)
Yet again you ask the most reasonable and necessary question (now I don't know precise data by heart and won't give you unprecise information but I am educative in attitude towards you and help you learn how to learn for yourself). There is a diagram that is followed by every chemist with respect to the relationship between negative pressure (vacuum) and temperature, you have to seek this for yourself (I promise you will not have much trouble finding it). The point is to check the data and have the vacuum at least slightly below the normal (ambient) b.p. of your compound to be distilled (foaming spoiler alert). I also reccomend Vogel's practical organic chemistry book that you can download as .pdf without much seeking (it also has the above mentioned diagram and it explains pretty much everything you need to know with regard to preparative chemistry). You will become a much better profesiional chemist after reading the handfull of relevant material from this reference. I just gave you the best tip I give to anyone. Remember that the knowledge you work for, it forever will be yours.
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.
(step 1.). I understand it that to just put those ingridients together in flask and start cooking... And my questions are:
1) Doesn't the temperature will grow up dramatically, spontanously after adding HgCl2(or HgNO3), and need to control it to avoid boiling over?
2) Shouldn't I prepare an aluminium amalgam before adding the rest of ingridients (P2P, EtOH, Methylamine)? Or it doesn't matter and I can just put in the flask all ingridients together and start reflux?
3) Is there any difference what alcohol will I use as a reaction solvent (for example methanol or isopropanol instead of ethanol)?
(step 1.). I understand it that to just put those ingridients together in flask and start cooking... And my questions are:
1) Doesn't the temperature will grow up dramatically, spontanously after adding HgCl2(or HgNO3), and need to control it to avoid boiling over?
2) Shouldn't I prepare an aluminium amalgam before adding the rest of ingridients (P2P, EtOH, Methylamine)? Or it doesn't matter and I can just put in the flask all ingridients together and start reflux?
3) Is there any difference what alcohol will I use as a reaction solvent (for example methanol or isopropanol instead of ethanol)?
there's a video of this synthesis that may show the details for second question.
7. Methamphetamine free base is dissolved in x3 volume of dry acetone.
Can acetone replaced with ethanol or methanol or dcm?
7. Methamphetamine free base is dissolved in x3 volume of dry acetone.
Can acetone replaced with ethanol or methanol or dcm?
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