作业帮苯乙腈乙酸乙脂甲醇钠反应二小时ph也调了也过滤了静止几小时,怎么还是一杯水什么物体也没有.哪里做了,在什么步骤后才结晶.
来源：学生作业帮 编辑：拍题作业网作业帮 分类：英语作业 时间：2024/05/01 11:07:12
苯乙腈乙酸乙脂甲醇钠反应二小时ph也调了也过滤了静止几小时,怎么还是一杯水什么物体也没有.哪里做了,在什么步骤后才结晶.
这个反应是需要加热的,而且醇钠的质量要保证.下边是一个专利的操作,不同之处是使用了现场制备的乙醇钠,
25 g (0.213 mol) portion of phenylacetonitrile and 33 ml of ethyl acetate were added to an ethanol solution of sodium ethoxide prepared from ethanol (150 ml) and 6.38 g (0.277 mol) of metallic sodium and then heated under reflux for 3 hours.After cooling,this was concentrated under a reduced pressure,and the thus obtained residue was mixed with water and dichloromethane to separate the organic layer.This was washed with 1 N hydrochloric acid and brine and dried over magnesium sulfate,and then the solvent was evaporated.The thus obtained residue was applied to a silica gel column chromatography to obtain 3.15 g (9percent) of the title compound as a colorless oily substance from a n-hexane-ethyl acetate (5:1-->3:1 v/v) eluate.MS (FAB)m/z:160 (M+1)+.1H-NMR (CDCl3)δ:2.27 (3H,s),4.68 (1H,s),7.36-7.52 (5H,m).
25 g (0.213 mol) portion of phenylacetonitrile and 33 ml of ethyl acetate were added to an ethanol solution of sodium ethoxide prepared from ethanol (150 ml) and 6.38 g (0.277 mol) of metallic sodium and then heated under reflux for 3 hours.After cooling,this was concentrated under a reduced pressure,and the thus obtained residue was mixed with water and dichloromethane to separate the organic layer.This was washed with 1 N hydrochloric acid and brine and dried over magnesium sulfate,and then the solvent was evaporated.The thus obtained residue was applied to a silica gel column chromatography to obtain 3.15 g (9percent) of the title compound as a colorless oily substance from a n-hexane-ethyl acetate (5:1-->3:1 v/v) eluate.MS (FAB)m/z:160 (M+1)+.1H-NMR (CDCl3)δ:2.27 (3H,s),4.68 (1H,s),7.36-7.52 (5H,m).
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