反应详情

A solution of diethyl ethoxycarbonylmethylphosphonate (3.3 g) in anhydrous tetrahydrofuran (20 ml) is added dropwise to a suspension of sodium hydride (60%, oily) (676 mg) in anhydrous tetrahydrofuran (30 ml) under a nitrogen atmosphere and ice cooling, and further a solution of ethyl 4-tolylglyoxylate (2.96 g) in anhydrous tetrahydrofuran (22 ml) is added dropwise thereto. The mixture is stirred at room temperature for 30 minutes, a 10% aqueous citric acid solution is added to the reaction mixture, and the whole is extracted with ether. The organic layer is washed with water and saturated brine successively, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting residue is purified by silica gel column chromatography to give 3.57 g (88%) of diethyl 2-(4-tolyl)maleate.

1. extractionthe whole is extracted with ether
2. washThe organic layer is washed with water and saturated brine successively
3. dry with materialdried over anhydrous magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. customThe resulting residue is purified by silica gel column chromatography