反应详情

To the above toluenic solution containing levobunolol as free base, 16 ml ethanol and the stoichiometric amount of hydrogen chloride were added. The stirred mixture was cooled below 10° C. and kept at this temperature for one hour. The precipitated solid was filtered, washed with toluene, recrystallized twice from 43 ml ethanol and dried to give 10.0 g (51% yield) of levobunolol hydrochloride having a rotary power at 25° C. below -19°.

1. temperatureThe stirred mixture was cooled below 10° C.
2. filtrationThe precipitated solid was filtered
3. washwashed with toluene
4. customrecrystallized twice from 43 ml ethanol
5. customdried