反応 #417945

反応方程式

5-bromo-2-ethoxy-pyridine

urea hydrogen peroxide

→

3-Bromo-6-ethoxy-2-methoxy-pyridine

溶媒

DCM

反応条件

後処理

1. 1
   workup.ADDITIONare added
2. 2
   温度Afterwards cooling
3. 3
   その他is removed
4. 4
   その他The solvent is removed in vacuo, water
5. 5
   workup.ADDITIONis added
6. 6
   抽出the resulting mixture is extracted with DCM
7. 7
   乾燥layers are dried over MgSO4
8. 8
   ろ過filtered
9. 9
   その他the sovent is removed in vacuo
10. 10
    その他The crude product is purified by column chromatography (silica gel, DCM/MeOH)

実験手順

To 5.00 g (24.7 mmol) 5-bromo-2-ethoxy-pyridine in 50 mL DCM are added 4.66 g (49.5 mmol) urea hydrogen peroxide. Then the mixture is chilled to 0° C. before 6.88 mL (49.5 mmol) TFA anhydride are added. Afterwards cooling is removed and the resulting mixture is stirred over night while the temperature raises to r.t. The solvent is removed in vacuo, water is added and the resulting mixture is extracted with DCM. The combined org. layers are dried over MgSO4, filtered and the sovent is removed in vacuo. The crude product is purified by column chromatography (silica gel, DCM/MeOH).

出典