反应详情

温度

0 °C

Lithium bis(trimethylsilyl)amide (7.79 mL, 7.79 mmol) was added to methyl 2-(3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)acetate (Intermediate 2-7; 2.2 g, 7.08 mmol) in THF (50 mL) cooled to 0° C. under nitrogen. The resulting solution was stirred at 0° C. for 30 minutes. Next methyl iodide (0.530 mL, 8.50 mmol) was added and the reaction stirred for 30 minutes Ammonium chloride (satd) (50 mL) was added with vigorous stirring, ethyl acetate (100 mL) and water (50 mL) were added and the organic phase separated, washed with water (50 mL) and saturated brine (50 mL). The organic layer was dried over MgSO4, filtered and evaporated to afford crude product. The crude product was purified by flash silica chromatography, elution gradient 0 to 40% EtOAc in isohexane. Pure fractions were evaporated to dryness to afford methyl 2-(3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)propanoate (1.290 g, 56.1%) as a colourless oil.

1. additionwere added
2. customthe organic phase separated
3. washwashed with water (50 mL) and saturated brine (50 mL)
4. dry with materialThe organic layer was dried over MgSO4
5. filtrationfiltered
6. customevaporated
7. customto afford crude product
8. customThe crude product was purified by flash silica chromatography, elution gradient 0 to 40% EtOAc in isohexane
9. customPure fractions were evaporated to dryness