反应详情

温度

-70 °C

14.5 g of 1-bromo-3,5-difluoro-4-(1-methylheptyloxy)benzene from step 1 were dissolved in 150 ml of diethyl ether and cooled to −70° C. At this temperature, with cooling, firstly 31.0 ml of a 15% solution of butyllithium in n-hexane were slowly added dropwise, the mixture was stirred at the same temperature for 1 h, and then 5.6 ml of trimethyl borate were slowly added dropwise, and the mixture was stirred for a further h. The temperature of the reaction solution was slowly allowed to rise to −10° C. The mixture was then hydrolysed with distilled water, and the pH was adjusted to 2 using hydrochloric acid. The organic phase was separated off, and the aqueous phase was extracted with MTB ether. The product was subjected to conventional purification and dried over Na2SO4, giving 13.9 g of 3,5-difluoro-4-(1-methylheptyloxy)phenylboronic acid.

1. temperatureAt this temperature, with cooling
2. stirringthe mixture was stirred for a further h
3. customto rise to −10° C
4. customThe organic phase was separated off
5. extractionthe aqueous phase was extracted with MTB ether
6. customThe product was subjected to conventional purification
7. dry with materialdried over Na2SO4