反应详情

A mixture of 5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-acetonitrile (1.00 g), ethanol (20.0 mL) and water (1.00 mL) is treated with concentrated sulfuric acid (10.0 mL), refluxed for 15 minutes, and poured into an ice-water mixture. The resultant aqueous mixture is extracted with methylene chloride. The combined organic extracts are washed sequentially with water, saturated sodium hydrogen carbonate solution and water, dried over anhydrous sodium sulfate, and concentrated in vacuo to obtain an orange foam. Column chromatography of the foam using silica gel and a 10% ethyl acetate in methylene chloride solution gives the title product as a solid which is identified by NMR spectral analysis.

1. temperaturerefluxed for 15 minutes
2. extractionThe resultant aqueous mixture is extracted with methylene chloride
3. washThe combined organic extracts are washed sequentially with water, saturated sodium hydrogen carbonate solution and water
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated in vacuo
6. customto obtain an orange foam