Hydrochloric Acid → 3-Chloro-5,6-dihydroxy-4-nitro-1-benzothiophene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To the solution of 3-chloro-5-hydroxy-6-methoxy-4-nitro-benzo[b]thiophene-2-carboxylic acid (0.2 g), pyridine (6.3 ml) in ethyl acetate (5 ml) was gradually added aluminum trichloride (0.32 g). The reaction mixture was refluxed at 90° C. for two hours. To the warm reaction (60° C.) solution was added the mixture of concentrated hydrochloric acid and ice (1:1). The product was extracted into ethyl acetate, dried and evaporated. The residue was treated with diethyl ether and the resultant solid was filtered.

Provenance & Evidence