反应详情

Under cooling on ice, 70 ml of hydrochloric acid/methanol was added to 70 ml of 9.47 g of 5,7-bis(methoxymethoxy)-2-methylthiochromone (30.35 mmol) in THF, and the mixture was stirred overnight at room temperature. After addition of water, the reaction solution was extracted twice with ethyl acetate, and the organic layer was washed with saturated NaCl water and dried over sodium sulfate anhydride. The solvent was distilled off under reduced pressure, to give 6.88 g of 5,7-dihydroxy-2-methylthiochromone. This product was subjected without purification to the following reaction.

1. extractionthe reaction solution was extracted twice with ethyl acetate
2. washthe organic layer was washed with saturated NaCl water
3. dry with materialdried over sodium sulfate anhydride
4. distillationThe solvent was distilled off under reduced pressure