反应详情

100 mg (0.27 mmol) of ethyl 6-[N-(2-chloro-4-fluorophenyl)sulfamoyl]-3-oxo-1-cyclohexene-1-carboxylate obtained in Example 7 and 69 mg (0.35 mmol) of (R)-2,3-dihydroxypropyl benzoate were dissolved in 2 ml of dichloromethane and 0.19 ml (1.05 mmol) of isopropoxytrimethylsilane and 2 μl (0.014 mmol) of trimethylsilyl trifluoromethanesulfonate were sequentially added thereto with stirring under ice-cooling, followed by stirring at the same temperature for 1 hour. Water was added to the reaction solution and the mixture was extracted with ethyl acetate. The organic layer was washed with water and dried over anhydrous magnesium sulfate, followed by concentration under reduced pressure. The residue was subjected to silica gel column chromatography (solvent; hexane:ethyl acetate 1:1), to give 121 mg of ethyl (2R)-2-benzoyloxymethyl-8-[N-(2-chloro-4-fluorophenyl)sulfamoyl]-1,4-dioxaspiro[4.5]dec-6-ene-7-carboxylate as a pale yellow oil (yield: 81%).

1. temperaturecooling
2. stirringby stirring at the same temperature for 1 hour
3. extractionthe mixture was extracted with ethyl acetate
4. washThe organic layer was washed with water
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationfollowed by concentration under reduced pressure