Carbon Dioxide → HCID 70598027, compound

Participants

Reaction Steps

3-ethyl-2-methyl-thiophene [W. Steinkopf, A. Merckoll and H. Straunch, Liebigs Ann. Chem. 545,45 (1940)] was reacted, analogous to 2-methyl-thiophene (see Example 5) with phosphorus pentachloride and chlorosulfonic acid, and the resulting sulfochloride was treated with tert.butylamine. By metalizing with n-butyl-lithium and carboxylating with carbon dioxide, also in analogy to the preparation of 5-methyl-2-(N-tert.butyl) sulfamoyl-thiophene-3-carboxylic acid, 4-ethyl-5-methyl-2-(N-tert.butyl) sulfamoyl-thiophene-3-carboxylic acid was obtained. Rf -value: 0.27 (TLC-prefabricated plates, silica gel 60 F254, thickness of the layer 0.25 mm, eluant:ethylene chloride/ethyl acetate/glacial acetic acid 100:30:5);

Provenance & Evidence