Sulfuric Acid → Methyl 3-hydroxy-5-(trifluoromethyl)thiophene-2-carboxylate

Participants

Reaction Steps

A solution of 1M potassium hydroxide in methanol (30 ml) is added to a cooled mixture of 5A (4.6 g), methyl thioglycolate (2.46 g) and methanol (10 ml). The resulting reaction mixture was stirred for 24 hours at room temperature. Then the mixture was poured on ice and acidified with 6N sulfuric acid (pH=2). The mixture is extracted with diethyl ether twice. The combined organic phases were washed with water and dried. The mixture was concentrated and the residue is distilled under reduced pressure to yield the product as a clear liquid (3.4 g, 65%) with a boiling point of 42-45° C. at 0.10 mm.

Provenance & Evidence