Réaction #955962

ord-2b6180bbf40a429c873ccf89181867b6

Équation de réaction

O=S(=O)(O)O
sulfuric acid
CCOC(=O)c1cscc1C(=O)OCC
diethyl thiophene-3,4-dicarboxylate
CC[O-].[Na+]
sodium ethoxide
CCOC(C)=O
ethyl acetate
O=C1CC(=O)c2cscc21
4H-cyclopenta[c]thiophene-4,6(5H)-dione

Solvants

Conditions de réaction

Conditions détaillées
See reaction.notes.procedure_details.

Traitement

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

Mode opératoire

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.

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US08968885B2uspto-grants-2015_03