反应详情

温度

-78 °C

tert-Butyllithium (1.7 M solution in hexane, 36.2 ml, 61.6 mmol) is added dropwise to a solution of 3,5-dimethylbiphenyl (7.27 g, 28 mmol) in dry tetrahydrofuran (150 ml) at −78° C. under an atmosphere of nitrogen. The reaction mixture is stirred at −78° C. for 30 minutes, then trimethylborate (9.54 ml, 84 mmol) is added. The resulting mixture is stirred at −78° C. for 30 minutes and then allowed to warm to room temperature. The reaction mixture is acidified with 10% aqueous hydrochloric acid solution and extracted with diethyl ether (2×150 ml). The organic layers are combined, dried over anhydrous magnesium sulfate, filtered and the filtrate is evaporated under reduced pressure to give a yellow solid. Trituration with isohexane gives 3,5-dimethylbiphen-4-ylboronic acid as a white powder (5.89 g).

1. stirringThe resulting mixture is stirred at −78° C. for 30 minutes
2. temperatureto warm to room temperature
3. extractionextracted with diethyl ether (2×150 ml)
4. dry with materialdried over anhydrous magnesium sulfate
5. filtrationfiltered
6. customthe filtrate is evaporated under reduced pressure
7. customto give a yellow solid