m-Chloroperbenzoic acid → Ethyl 7-acetoxy-2,3-dihydro-1,4-benzodioxin-2-carboxylate
反応式
C([C:4]1[CH:5]=[CH:6][C:7]2[O:12][CH2:11][CH:10]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[O:9][C:8]=2[CH:18]=1)(=O)C.ClC1C=CC=[C:22]([C:26]([O:28]O)=[O:27])C=1>ClCCl>[C:26]([O:28][C:4]1[CH:5]=[CH:6][C:7]2[O:12][CH2:11][CH:10]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[O:9][C:8]=2[CH:18]=1)(=[O:27])[CH3:22]参加物
4
実験手順
4 g (16 mmol) of the ester obtained in Step C are dissolved in 60 ml of anhydrous dichloromethane; 6.1 g (35.4 mmol) of meta-chloroperbenzoic acid are then added to the medium. After 18 hours of reflux under an inert atmosphere, the mixture is cooled and then hydrolysed with ice-cold water. The aqueous phase is extracted with dichloromethane; the organic phase is then washed several times with a saturated solution of sodium hydrogen carbonate. After drying over magnesium sulphate and evaporation of the solvent in vacuo, the residue obtained is purified on a silica column (eluant: AcOEt/PE: 30/70) to yield the title ester in the form of a syrup.