Flunarizine drug intermediates 4,4-difluorophenyl methanone synthesis method

摘要

#$%^&*AU2016102174A420170216.pdf#####ABSTRACT Flunarizine drug intermediates 4,4-difluorophenyl methanone synthesis method, comprising the following steps: equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, the reaction vessel was added 0.21-0.23mol cuprous bromide, 200ml carbon disulfide, controlling the stirring speed at 130-160rpm, the temperature of the solution is reduced to 7--90 C, 0.21mol fluorobenzene (2) was added drop by drop, after the addition the solution temperature was raised to 35--40'C, stirring for 4-5h, until no gas generated so far, standing for 30-32h, generating intermediate (3), 120-150ml saline solution was added, carbon disulfide was distilled off, a small amount of water was added, vacuum distillation until no oily component distillated, and the organic layer was separated, and the aqueous layer was extracted 5-8 times with nitromethane solution, combined the organic layers, dehydrated with activated alumina, the temperature of the solution is reduced to 3--60C, precipitated crystals were filtered and dried, got white flaky crystals 4,4-difluorophenyl methanone.