Hydrochloric Acid → 5-(Hydroxymethyl)thiophene-2-carboxylic acid

Participants

Reaction Steps

To a solution of 5-formylthiophene-2-carboxylic acid (2.000 g, 12.81 mmol) in tetrahydrofuran (25 ml) was added water (2.5 ml). Sodium borohydride (1.453 g, 38.42 mmol) was added by small portions, and the mixture was stirred at room temperature for 1 hr. The reaction mixture was adjusted to pH about 8 by adding a small amount of 1M hydrochloric acid, and washed with ethyl acetate. The aqueous layer was adjusted to pH 2-2.5 by adding concentrated hydrochloric acid, and saturated with sodium chloride. The mixture was extracted 3 times with ethyl acetate. The combined organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated to dryness to give 5-(hydroxymethyl)thiophene-2-carboxylic acid (1.430 g, yield 70.6%) as a yellow solid.

Provenance & Evidence