反应详情

Under nitrogen and at 0-5° C., 0.7 g (2 mmol) of 2-methyl-3-(5-chloromethyl-4,5-dihydroisoxazol-3-yl)-4-methyl-sulfonylbenzoyl chloride in 40 ml of acetonitrile was added dropwise to 0.28 g (2 mmol) of bicyclo[3.2.1]octane-2,4-dione and 0.4 g (4 mmol) of triethylamine in 40 ml of acetonitrile, and the mixture was stirred at room temperature for 4 hours. 1 drop of trimethylsilyl cyanide and 0.05 g of potassium carbonate were then added, and the mixture was stirred at 40° C. for 2 hours and then at room temperature for 12 hours. Following this, the solvent was removed, the residue was taken up in ethyl acetate and the solution was extracted repeatedly with 5% strength potassium carbonate solution. The combined extracts were then adjusted to pH 2-3 using 10% strength hydrochloric acid and extracted repeatedly with methylene chloride. These combined organic extracts were then washed with water and dried, and the solvent was removed. The oily yellow residue was chromatographed over silica gel (mobile phase: methylene chloride/methanol=99/1 to 97/3). This gave 0.4 g (44% of theory) of the title compound of melting point 98-103° C.

1. stirringthe mixture was stirred at 40° C. for 2 hours
2. waitat room temperature for 12 hours
3. customwas removed
4. extractionthe solution was extracted repeatedly with 5% strength potassium carbonate solution
5. extractionextracted repeatedly with methylene chloride
6. washThese combined organic extracts were then washed with water
7. customdried
8. customthe solvent was removed
9. customThe oily yellow residue was chromatographed over silica gel (mobile phase: methylene chloride/methanol=99/1 to 97/3)