The usual Manske process leaves behind some amount of salt. It can be minimized, but always be there...
...so I was thinking about salting harmalas by adding alcoholic HCl to alcoholic solution of harmine, harmaline or tetrahydroharmine free base.
The acidity would be tested by dropping the mixture sample on a blot of nitrazine yellow solution (a sensitive pH indicator).
Once fully salted, the alcohol would be evaporated in a rotavap (to save the alcohol) and the concentrated residue fully dried in a dish, yielding harmala hydrochlorides free of salt. Most of the excess water and HCl will get distilled off in the process.
As for the choice of alcohol, I would use methanol or isopropanol, as these are easily available to me. Methanol has lowest boiling point but is most toxic. Isopropanol has highest b.p. but can remove excess water by distilling off its azeotrope (91% IPA). Ethanol is somewhere in the middle.
What do you think about this process?
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