| 摘要 |
Dilazep drug intermediates 3-chloro-3,4,5-trimethoxy-propyl benzoate synthesis method , comprising the following steps: equipped with a stirrer and a reflux condenser, the reaction vessel was added 0.81mol 3,4,5-trimethoxy-benzoic acid (2), 1.51-1.53mol 1 amino-3-chloropropane (3), 1.3 L acetonitrile solution , raised the solution temperature to 60-65 C, refluxed for 3-5h, added 0.52mol sodium sulfite solution, maintaining stirring speed 130-170rpm, continued the reaction for 14-15h, reducing the temperature of the solution to 10 - 15 C, filtered and the filtrate evaporated under reduced pressure, recovered the solvent, the residue was added 500ml cyclohexane solution, the solution temperature is raised to 70 - 75 C, maintained 90-120min, the crystal was cooled, suction filtered, washed with salt solution, washed with ethyl acetate solution to precipitate, dehydrated with dehydrating agent, recrystallized in propionitrile solution, got crystals of 3-chloro-3,4,5-trimethoxy-propyl- benzoate . |
