Eugenol Demethylation with Pyridine HCl (by Startinout) [4]
Basically the microwave demethylation fucking rocks, as far as ease goes, but the downside is because you need 5:1 pyridine HCl:eugenol.
I made my pyridine HCl by gassing pyridine with anhydrous HCl gas, this was pretty easy (just gassed it for a while, some crystals formed but it was
quite hot so i froze it, many more crystals formed, filtered it, washed with ether, then put the crystals on the bench to dry, came back, almost no
crystals left and very sloppy, note-they are very deliquescent and they sublime so put them in a closed container immediately post production.
Microwave Demethylation
All I did was added eugenol in the weight ratio five parts pyridine HCl two parts eugenol (this is molar 5:1), put this in a round bottom flask,
stoppered it, microwaved in a normal microwave on medium low (the paper uses 215 watt oven) for two minutes, the stuff melts and turns quite hot, it
was removed, cooled under the tap until it was room temp again (just felt it with my hand), then microwaved again for two minutes etc etc, this
process was repeated six times, the more you do it the hotter it gets each time. After the sixth time i cooled it again, poured some cold water from
the fridge into into it and extracted it three times with ether, pooled the ether extracts, removed the ether on the rotavap, the residue had no smell
of clove oil whatsoever, just the smokey smell of the demethylated product, so i assumed quantitative yeild cause I couldn't be fucked vac
distilling a room temp solid and/or GC'ing it, also the methylation requires an excess of all other reagants anyway.
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