反应详情

温度

0 °C

An excess of 1.6M n-BuLi in hexane (14 mL, 22.3 mmol) was added to a solution of 3-bromo-9-(diberizo[b,d]thiophen-4-yl)-9H-carbazole (8.7 g, 20.3 mmol) in 100 ml dry tetrahydrofuran at −78° C. under N2. The reaction mixture was then maintained at 0° C. for 1 h before cooling to −78° C. Trimethylborate (2.8 g, 26.4 mmol) was added dropwise; the solution was then warmed slowly to room temperature and stirred for 24 h. 2N HCl (50 ml) was added and then the mixture was stirred for a further 1 h. The reaction mixture was extracted with ethyl acetate and water, dried with anhydrous magnesium sulfate, the solvent was evaporated in vacuum, and the residue was crystallized from n-hexane to give the 9-(dibenzo[b,d]thiophen-4-yl)-9H-carbazol-3-ylboronic acid 4.7 g (59%)

1. temperaturebefore cooling to −78° C
2. temperaturethe solution was then warmed slowly to room temperature
3. stirringthe mixture was stirred for a further 1 h
4. extractionThe reaction mixture was extracted with ethyl acetate and water
5. dry with materialdried with anhydrous magnesium sulfate
6. customthe solvent was evaporated in vacuum
7. customthe residue was crystallized from n-hexane