反应详情

温度

50 °C

Into a 200 mL flask equipped with a reflux condenser, 2.58 g of sodium borohydride and 25 g of dimethoxyethane were charged. The obtained mixture was adjusted to 50° C. and then, a solution obtained by mixing 6.10 g of 2,3,5,6-tetrafluoroterephthalic acid with 20 g of dimethoxyethane was added dropwise thereto over 1 hour while stirring. The obtained mixture was stirred for 7 hours at 60° C. To the obtained reaction mixture, 20 g of toluene was added followed by cooling to 50° C. Eight point five grams of 35% by weight hydrochloric acid was added dropwise thereto over 1 hour to stir at 60° C. for 6 hours. To the obtained mixture, 30 g of water was added followed by separating to an organic layer and an aqueous layer. The aqueous layer was extracted twice with 30 g of ethyl acetate. The obtained organic layers were mixed and washed with 10 g of a saturated aqueous potassium carbonate solution and then with 10 g of water. The organic layer was concentrated and the obtained solids were recrystallized with toluene and hexane to obtain white powder crystals of 2,3,5,6-tetrafluorobenzenedimethanol. The crystals were analyzed by liquid chromatography absolute calibration curve method to find out that the purity thereof was 95.1%. Yield: 95%.

1. customInto a 200 mL flask equipped with a reflux condenser
2. customwas adjusted to 50° C.
3. customa solution obtained
4. additionwas added dropwise
5. stirringThe obtained mixture was stirred for 7 hours at 60° C
6. additionwas added
7. stirringover 1 hour to stir at 60° C. for 6 hours
8. customby separating to an organic layer
9. extractionThe aqueous layer was extracted twice with 30 g of ethyl acetate
10. additionThe obtained organic layers were mixed
11. washwashed with 10 g of a saturated aqueous potassium carbonate solution
12. concentrationThe organic layer was concentrated
13. customthe obtained solids were recrystallized with toluene and hexane