Reaktion #955962

Reaktionsgleichung

sulfuric acid

diethyl thiophene-3,4-dicarboxylate

sodium ethoxide

ethyl acetate

→

4H-cyclopenta[c]thiophene-4,6(5H)-dione

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONis added through syringe pump over one hour
2. 2
   TemperaturThe mixture was further heated for a few hours
3. 3
   TemperaturThe mixture is heated at this temperature for one hour

Vorschrift

In a dry 3-neck flask with an argon inlet and a water condenser, diethyl thiophene-3,4-dicarboxylate (3.7 g, 16.2 mmol) is mixed with sodium ethoxide (1.1 g, 16.2 mmol). After heating to 100° C. ethyl acetate (1.4 g, 16.2 mmol) is added through syringe pump over one hour. The mixture was further heated for a few hours. The residue was redissolved in water at 70° C. and concentrated sulfuric acid is added (1 mL). The mixture is heated at this temperature for one hour to ensure complete decarboxylation.

Quelle