Dimethylformamide → 5-Methoxy-3-stilbene carboxylic acid methyl ester
反応式
[H-].[Na+].[CH2:3](P(=O)(OCC)OCC)[C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[CH3:18][O:19][C:20](=[O:31])[C:21]1[CH2:22][C:23]([O:29][CH3:30])([CH:26]=[CH:27][CH:28]=1)C=O.[CH3:32]N(C)C=O>>[CH3:18][O:19][C:20]([C:21]1[CH:28]=[C:27]([CH:32]=[CH:3][C:4]2[CH:5]=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:26]=[C:23]([O:29][CH3:30])[CH:22]=1)=[O:31]参加物
5
実験手順
To a slurry of 1.0 mole of sodium hydride in one liter of N,N-dimethylformamide is added 1.0 mole of diethyl benzylphosphonate. The reaction mixture is stirred for one hour and then a solution of 1.0 mole of 3-methoxyisophthalaldehydic acid methyl ester in a minimal amount of dimethylformamide is added. The reaction mixture is stirred for several hours and is then added to ether-water. The ether extract is washed several times with water, dried over magnesium sulfate and evaporated to a residue. The residue is purified via crystallization from hexane to yield 5-methoxy-3-stilbene carboxylic acid methyl ester. The free acid is obtained by refluxing a solution of 1.0 mole of the methyl ester in one liter of 1 N methanolic sodium hydroxide for 4-5 hours. The reaction mixture is evaporated to a residue which is added to ethyl acetate. The ethyl acetate solution is extracted with several portions of water. The combined aqueous extract is neutralized with 1 N hydrochloric acid and extracted with several portions of ethyl acetate. This organic extract is dried over magnesium sulfate and evaporated to a residue. The residue is purified by crystallization from hexane to yield 5-methoxy-3-stilbene carboxylic acid.