反应详情

温度

0 °C

n-Butyllithium (2.5M in hexanes, 5.78 mL) was added to a solution of [2-(3-bromofuran-2-yl)-ethoxy]-tert-butyldimethylsilane (Intermediate 34, 4.01 g) in diethyl ether (130 mL) at −60° C. under nitrogen and the resultant mixture was stirred for 30 minutes. Trimethylborate (2.73 g) was then added to the mixture and it was stirred for a further 10 minutes. The reaction mixture was warmed to 0° C., water was added and the mixture was stirred for 15 minutes. The organic layer was separated, dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 0-30% to give 2-[2-(tert-butyldimethylsilanyloxy)-ethyl]-furan-3-yl-boronic acid (1.23 g) as a colourless oil.

1. stirringthe mixture was stirred for 15 minutes
2. customThe organic layer was separated
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. customThe filtrate was evaporated to dryness
6. customthe residue was purified by chromatography on silica
7. washeluting with a mixture of ethyl acetate and cyclohexane with a gradient of 0-30%