反应详情

To 5-formyl-4-hydroxy-3-methyl-benzofuran-2-carboxylic acid tert-butyl ester (430 mg, 1.56 mmol) was added 8 mL of THF, followed by sodium cyanoborohydride (117 mg, 1.87 mmol) in one portion. The solution was stirred at room temperature for 1 h and then placed in a 65° C. oil bath overnight. The solvent was removed under vacuum and water was added. The mixture was extracted with ethyl acetate. Removal of the solvent gave the crude product, which was purified by column chromatography to give 200 mg of 4-hydroxy-5-hydroxymethyl-3-methyl-benzofuran-2-carboxylic acid tert-butyl ester was obtained as a yellow semi-solid.

1. customplaced in a 65° C.
2. customovernight
3. customThe solvent was removed under vacuum and water
4. additionwas added
5. extractionThe mixture was extracted with ethyl acetate
6. customRemoval of the solvent
7. customgave the crude product, which
8. customwas purified by column chromatography