反応 #302855

反応方程式

boron tribromide

compound 15

6-bromo-4′-methoxyflavone

→

compound 16

6-bromo-4′-hydroxyflavone

溶媒

dichloromethane

dichloromethane

反応条件

後処理

1. 1
   温度under cooling on ice
2. 2
   その他the obtained mixture was then reacted
3. 3
   その他After completion of the reaction
4. 4
   その他purified water (100 ml)
5. 5
   workup.ADDITIONwas added to the reaction solution
6. 6
   抽出the dichloromethane layer was extracted
7. 7
   乾燥The extract was dried over anhydrous sodium sulfate
8. 8
   workup.DISTILLATIONthe solvent was then distilled away under reduced pressure

実験手順

A dichloromethane solution (12 ml) that contained boron tribromide was slowly added to a dichloromethane solution (215 ml) that contained compound 15 (400 mg, 1.21 mmol) while stirring under cooling on ice, and the obtained mixture was then reacted. After completion of the reaction, purified water (100 ml) was added to the reaction solution, and the dichloromethane layer was extracted. The extract was dried over anhydrous sodium sulfate, and the solvent was then distilled away under reduced pressure. The residue was subjected to silica gel column chromatography using ethyl acetate/hexane (2/5) as an elution solvent, so as to obtain a product of interest, 6-bromo-4′-hydroxyflavone (compound 16). Yield: 50 mg (yield constant: 13.1%) 1H NMR (300 MHz, CDCl3) δ10.38 (s, 1H), 8.09 (s, 1H), 7.97-8.00 (m, 3H), 7.76 (d, J=9.0 Hz, 1H), 6.93-6.96 (m, 3H).

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