反应详情

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.

1. washwashed with ethyl acetate
2. additionby adding concentrated hydrochloric acid
3. extractionThe mixture was extracted 3 times with ethyl acetate
4. washThe combined organic layer was washed with saturated brine
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated to dryness