反应详情

温度

0 °C

To a solution of 1-bromo-4-chloro-2,5-difluorobenzene (200 mg, 0.879 mmol) in THF (10 mL) cooled to −10° C. was added isopropylmagnesium bromide (1M in THF, 1.055 mL, 1.055 mmol) dropwise and the reaction mixture was stirred at this temperature for 1 h. The reaction mixture was then warmed to 0° C. and stirred for another 1 h. The resultant mixture was again cooled to −10° C. and treated dropwise with a solution of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (196 mg, 1.055 mmol). The reaction mixture was allowed to warm up to room temperature and treated with a saturated solution of ammonium chloride (3 mL). The layers were separated and aqueous layer was extracted with dichloromethane (2×2 mL). The combined organic layer was dried over sodium sulfate, filtered and concentrated under reduced pressure to afford crude compound which was purified by column chromatography on a silica (7:3-Ethyl acetate:hexane) to afford 2-(4-chloro-2,5-difluorophenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (150 mg, 0.546 mmol, 62% yield) as an oil. 1H NMR (400 MHz, DMSO-d6) δ ppm 7.46-7.49 (m, 1H), 7.09-7.13 (m, 1H), 1.35 (s, 12H).

1. stirringstirred for another 1 h
2. temperatureto warm up to room temperature
3. customThe layers were separated
4. extractionaqueous layer was extracted with dichloromethane (2×2 mL)
5. dry with materialThe combined organic layer was dried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customto afford crude compound which
9. customwas purified by column chromatography on a silica (7:3-Ethyl acetate:hexane)