反応 #1166462

反応方程式

3-methoxy-4-hydroxy-7-acetoxy-2H-l-benzopyran-2-one

benzyl bromide

sodium carbonate

→

title compound

収率 37.0%

3-methoxy-4-benzyloxy-7-acetoxy-2H-1-benzopyran-2-one

収率 37.0%

溶媒

DMF

反応条件

後処理

1. 1
   ろ過The solid in the reaction mixture was filtered off
2. 2
   workup.ADDITIONthe filtrate was poured into 200 ml of water
3. 3
   抽出extracted with 500 ml of benzene
4. 4
   濃縮The organic layler was concentrated in vacuo
5. 5
   乾燥after drying over magnesium sulfate
6. 6
   その他to give oily residue
7. 7
   その他The residue was purified on silica gel column chromatography (eluent: benzene/ethyl acetate=7/3)

実験手順

To a mixture of 8.11 g of 3-methoxy-4-hydroxy-7-acetoxy-2H-l-benzopyran-2-one (27.8 mmol) and 5.71 g of benzyl bromide (33.4mmol) in 50 ml of DMF was added 4.61 g of sodium carbonate (33.4 mmol) under argon atmosphere, then the mixture was stirred at 50° for 2 hours. The solid in the reaction mixture was filtered off, the filtrate was poured into 200 ml of water and extracted with 500 ml of benzene. The organic layler was concentrated in vacuo after drying over magnesium sulfate to give oily residue. The residue was purified on silica gel column chromatography (eluent: benzene/ethyl acetate=7/3) to give 3.50 g of the title compound. (yield=33%)

出典