反应详情

A mixture of 0.17 g of N-methyl-3,4-dihydro-3-hydroxy-6-trifluoromethyl-2,2-dimethyl-2H-1-benzopyran-4-carbothioamide, 0.21 g of p-toluenesulfonyl chloride, and 10 ml of pyridine was heated at reflux for 4 hours. To the reaction mixture was added 2N hydrochloric acid, and the mixture was extracted with dichloromethane. The extract was dried over magnesium sulfate. The residue was purified by silica gel column chromatography (CH2Cl2 :methanol=100:1) and then recrystallized from a mixture of diethyl ether and n-hexane to obtain 44 mg of N-methyl-6-trifluoromethyl-2,2-dimethyl-2H-1-benzopyran-4-carboxamide represented by formula shown below.

1. temperaturewas heated
2. temperatureat reflux for 4 hours
3. extractionthe mixture was extracted with dichloromethane
4. dry with materialThe extract was dried over magnesium sulfate
5. customThe residue was purified by silica gel column chromatography (CH2Cl2 :methanol=100:1)
6. customrecrystallized from a mixture of diethyl ether and n-hexane