反応 #614837

反応方程式

(2,2-difluoro-1,3-benzodioxol-4-yl)boronic acid

Intermediate 195

(2,2-difluoro-1,3-benzodioxol-4-yl)boronic acid

sec-BuLi

cyclohexane

Methyl iodide

→

title compound

(2,2-difluoro-7-methyl-1,3-benzodioxol-4-yl)boronic acid

溶媒

THF

反応条件

後処理

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   workup.STIRRINGthe reaction mixture was stirred for 2 hours while the temperature
3. 3
   その他to reach room temperature
4. 4
   その他The reaction was quenched by addition of an aqueous 2N solution of HCl
5. 5
   workup.ADDITIONdiluted with ethyl acetate
6. 6
   その他The organic layer was collected
7. 7
   洗浄washed twice with brine
8. 8
   乾燥dried over Na2SO4
9. 9
   その他evaporated to dryness
10. 10
    その他Crystallization from n-heptane

実験手順

(2,2-difluoro-1,3-benzodioxol-4-yl)boronic acid (Intermediate 195, crude material) was dissolved in THF (20 mL) and the resulting solution cooled down to −78° C. sec-BuLi 1.4M solution in cyclohexane (17.4 ml, 24.36 mmol) was added dropwise and the reaction mixture was stirred for 1.5 hours at −78° C. Methyl iodide (4.6 ml, 73 mmol) was then added and the reaction mixture was stirred for 2 hours while the temperature was allowed to reach room temperature. The reaction was quenched by addition of an aqueous 2N solution of HCl and diluted with ethyl acetate. The organic layer was collected and then washed twice with brine, dried over Na2SO4 and evaporated to dryness. Crystallization from n-heptane afforded the title compound (150 mg) as white solid.

出典