| 摘要 |
Sodium valproate drug intermediates dipropyl cyanoacetic acid methyl ester synthesis method, comprising the following steps: equipped with a stiffer, a reflux condenser and a thermometer, the reaction vessel was added 1.73mol methyl cyanoacetate (2), 0.56 mol stannous chloride, 3.7-3.9mol 1-amino propane, 0.61mol sodium sulfite, controlling the stirring speed 110-150rpm, raised the solution temperature to 70 - 75 0C, held reflux for 60-90min, after the solution color deepened, warmed to 80 - 85 0C , continued for 3 - 4 h, then warmed to 90--95 0C, holding 2-3h, then warmed to 100--105 0C, holding 80-120min, and then reducing the solution temperature to 10 - 15 0C, 300ml potassium chloride solution was added to dissolve the solid, separated the organic layer, the aqueous layer was extracted with nitromethane solution for 3-5 times, and the combined organic layers and nitromethane layer was washed with salt solution, washed with toluene solution, dehydrated with dehydrating agent, recrystallized from ethyl acetate solution, got crystals dipropyl cyanoacetic acid methyl ester . |
