反应详情

Cesium carbonate (0.82 g) was added to a solution of 3-phenyl-2(5H)-furanone (0.88 g) in methanol (15 mL) and the mixture was stirred at room temperature for one hour and stripped of methanol. 2-Chloromethyl-4-isopropyl-6-methoxysaccharin (1.52 g) was added to a solution of the residue in dimethylformamide (15 mL) and the mixture was stirred at room temperature for two days. Silica gel (4.4 g) was added, volatiles were removed under vacuum, and the solid was subjected to flash chromatography on silica gel using ethyl acetate-hexane (3:7) as eluant. Recrystallization of the product from ethanol-ether gave 2-(2,5-dihydro-2-oxo-3-phenylfuran-4-yl)oxymethyl-4-isopropyl-6-methoxysaccharin as a colorless solid (0.45 g, 20% yield, m.r. 180°-182° C. ).

1. stirringthe mixture was stirred at room temperature for two days
2. additionSilica gel (4.4 g) was added
3. customvolatiles were removed under vacuum
4. customRecrystallization of the product from ethanol-ether