Reaktion #553136

Reaktionsgleichung

6-Hydroxycoumarin

Sodium hydride

hydrochloric acid

Ethyl 5-bromopentanoate

→

title compound

6-(4-ethoxycarbonylbutyl)oxycoumarin

Lösungsmittel

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe mixture was reacted for 15 min
2. 2
   ExtraktionThe mixture was extracted with ether
3. 3
   WaschenThe extract was washed with water, dried anhydrous magnesium sulfate
4. 4
   Sonstigeevaporated
5. 5
   SonstigeThe residue was purified by column chromatography on silica gel (n-hexane: ethyl acetate=4:1→2:1)

Vorschrift

6-Hydroxycoumarin (405 mg; prepared in reference example 25) was dissolved in dry dimethylformamide (6 ml). Sodium hydride (60 mg) was added to the solution. The mixture was reacted for 15 min. Ethyl 5-bromopentanoate (0.48 ml) was added dropwise to the reaction solution. The mixture was stirred for 1 hr at 60° C. Ice-water was added to the reaction solution. The mixture was acidified with 1N hydrochloric acid. The mixture was extracted with ether. The extract was washed with water, dried anhydrous magnesium sulfate and then evaporated. The residue was purified by column chromatography on silica gel (n-hexane: ethyl acetate=4:1→2:1) to give the title compound (398 mg) having the following physical data.

Quelle