反应详情

温度

100 °C

To 30 ml of ethanol was dissolved 2.0 g (10 mmol) of methyl benzo[1,2,5]thiadiazole-5-carboxylate, followed by the addition of 3.3 g of a 25% aqueous solution of sodium hydroxide and stirring at room temperature for 3 hours. To the reaction liquid was added 50 ml of water and a dilute hydrochloric acid to make pH of 2. Crystal precipitated was filtered off and dried under reduced pressure to obtain 1.7 g (yield: 92%) of benzo[1,2, 5]thiadiazole-5-carboxylic acid. In a separate reactor, 0.50 g (2.2 mmol) of 6,6-difluoro-5-methyl-5-hexenyl methanesulfonate and 0.43 g (2.4 mmol) of benzo[1,2,5]thiadiazole-5-carboxylic acid were dissolved in 7 ml of N,N-dimethylformamide, followed by the addition of 0.37 g (4.4 mmol) of sodium hydrogencarbonate and stirring at 100° C. for 3 hours. The reaction liquid was then poured in water and extracted with ethyl acetate. The organic layer was washed with water and a saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate and concentration under reduced pressure. The residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:19) to obtain 0.44 g (yield: 64%) of 6,6-difluoro-5-methyl-5-hexenyl benzo[1,2,5]thiadiazole-5-carboxylate.

1. customThe reaction liquid
2. extractionextracted with ethyl acetate
3. washThe organic layer was washed with water
4. dry with materialby drying over anhydrous magnesium sulfate and concentration under reduced pressure
5. customThe residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:19)