反应详情

19.8 g of the sodium borohydride was added to 60 ml of tetrahydrofuran, and, while the mixed solution was cooled on ice below 10° C., a solution obtained by dissolving 60 g (276 mmol) of 2,3-difluoro-6-nitrophenylacetic acid in 20 ml of tetrahydrofuran was dropped to the mixed solution through 1 hour. Then, 120 ml of tetrahydrofuran solution dissolving 90 ml of boron trifluoride ethyl ether complex was dropped to the reaction solution through 1 hour below 10° C. The solution was stirred for 15 minutes under cooled on ice and for 20 minutes at room temperature. To 1.5 l of methylene chloride, 1.2 l of ice/water, 84 g of sodium hydrogen carbonate was added, and, while well stirring this solution, the reaction solution was slowly added to this solution. The obtained solution was stirred overnight. The organic layer was separated from the solution, and after drying over magnesium sulfate, solvent was removed by distillation to obtain 61 g of oily 3,4-difluoro-2-(2-hydroxyethyl)nitrobenzene. To this oily material, 58 ml (414 mmol) of triethylamine and 500 ml of methylene chloride were added, and while cooling on ice, 100 ml of methylene chloride solution containing 19 ml (381 mmol) of acetyl chloride was dropped to the solution. After stirring for 1 hour and 80 minutes, 5 ml of acetyl chloride was further added to the mixture, and after 30 minutes, the mixture was washed with 200 ml of water twice. After drying over magnesium sulfate, the solvent was removed by distillation to obtain 76.5 g of 2-(2-acetoxyethyl)-3,4-difluoronitrobenzene.

1. temperaturewhile the mixed solution was cooled on ice below 10° C.
2. customa solution obtained
3. additionwas dropped to the mixed solution through 1 hour
4. additionwas dropped to the reaction solution through 1 hour below 10° C
5. stirringwhile well stirring this solution
6. additionthe reaction solution was slowly added to this solution
7. stirringThe obtained solution was stirred overnight
8. customThe organic layer was separated from the solution
9. dry with materialafter drying over magnesium sulfate, solvent
10. customwas removed by distillation