Any thoughts of that this eminence could did?
I think that he dissolved the 2b34m with a non polar solvent, maybe THF, DCM, make some washings with water maybe with bicarbonate, dried the solvent with magnesium sulfate and let it crystallise evaporating slowly the solvent.
I have some 2b34m from china that is brown and didn't obtain high yields. Maybe I will try to purify.