ok, I will publish my synthesis here for revision and advice.
step 4 changed: diphenylacetonitrile (50 g), 1-dimethylamino-2-chloropropane hydrochloride (50 g)(think can use any 1-dimethylamino-2-halopropane), 50% sodium hydroxide solution (80 g), water (40 ml), toluene (125 ml) and...
there is writeup from seller, main raw is mdmb-5br-inaca.
its safe mix all at once? 3 hour of mix enough?
after reaction possible add only a lot of cold brine and wait crystalization without dcm/ethanol/fridge?