Reaktion #1166462

Reaktionsgleichung

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

benzyl bromide

sodium carbonate

→

title compound

Ausbeute 37.0%

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

Ausbeute 37.0%

Lösungsmittel

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe solid in the reaction mixture was filtered off
2. 2
   workup.ADDITIONthe filtrate was poured into 200 ml of water
3. 3
   Extraktionextracted with 500 ml of benzene
4. 4
   EinengenThe organic layler was concentrated in vacuo
5. 5
   Trocknenafter drying over magnesium sulfate
6. 6
   Sonstigeto give oily residue
7. 7
   SonstigeThe residue was purified on silica gel column chromatography (eluent: benzene/ethyl acetate=7/3)

Vorschrift

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%)

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