Why can't one just use 200ml's and let it stir for another 24hrs, ensuring all the freebase gets in the non polar?
You could let it sit for a million years, but there is an equilibrium partition coefficient for the MDMA freebase b/t the MeOH/H2O and the toluene. In other words, you can only extract a certain percentage of the freebase with one extraction. To extract more, you must use fresh toluene and perform a second and third, ect. The reason that so much toluene is required, is that the freebase is pretty soluble in the aqueous layer due to the presence of the methanol. If you follow my workup procedure, there will be no methanol left, and the freebase will form a separate layer that can be removed with a sep funnel. Just to scavenge up any stray freebase, I go ahead and extract the aqueous layer with ~100 mL toluene once or twice.