反应详情

温度

2.5 °C

To a suspension of 5,7-dihydroxy-3,4-dihydro-2H-naphthalen-1-one (XXV, prepared as described in Scheme 3 above, 320 mg, 1.79 mmol) in dichloromethane (25 mL) was added diisopropylethylamine (925 mg, 7.16 mmol) at −5 to 0° C. To the resulting solution was then added trifluoromethanesulfonic anhydride (1.06 g, 3.76 mmol) dropwise over 5 minutes at this temperature. The resulting brown solution was stirred for 45 minutes at ˜0-5° C. and then warmed to room temperature and stirred for another 15 minutes. The reaction mixture was then diluted with dichloromethane (50 mL) and water (70 mL). The aqueous layer was separated and extracted with dichloromethane (25 mL). The combined organic extracts were washed with brine (100 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated under vacuum. The crude product was dissolved in dichloromethane (10 mL) and diluted with hexanes (50 mL). The brown solution was stored in the refrigerator for 15 h. The resulting solids were collected by filtration and washed with hexanes. After drying in the air, trifluoro-methanesulfonic acid 8-oxo-4-trifluoromethanesulfonyloxy-5,6,7,8-tetrahydro-naphthalen-2-yl ester (0.548 g, 69%) was obtained as a light brown solid: EI(+)-HRMS m/e calcd. for C12H8F6O7S2 (M+) 442.9616, obsd. 442.9618.

1. temperaturewarmed to room temperature
2. stirringstirred for another 15 minutes
3. customThe aqueous layer was separated
4. extractionextracted with dichloromethane (25 mL)
5. washThe combined organic extracts were washed with brine (100 mL)
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated under vacuum
9. dissolutionThe crude product was dissolved in dichloromethane (10 mL)
10. additiondiluted with hexanes (50 mL)
11. waitThe brown solution was stored in the refrigerator for 15 h
12. filtrationThe resulting solids were collected by filtration
13. washwashed with hexanes
14. customAfter drying in the air