反应详情

3-Methoxycatechol (25 g) was dissolved in benzene, and dimethoxyacetal (35 ml) and a catalytic amount of p-toluenesulfonic acid were added thereto, followed by heating at reflux for 6 hours. After being allowed to stand for cooling, the mixture was adjusted to alkaline with an aqueous solution of sodium hydroxide, followed by extraction with ether. The organic layer was washed with a saturated saline and dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=99/1) to give Compound IIbk-a (19.4 g, 60.5%) as a white solid.

1. temperatureby heating
2. temperatureat reflux for 6 hours
3. temperaturefor cooling
4. extractionfollowed by extraction with ether
5. washThe organic layer was washed with a saturated saline
6. dry with materialdried over magnesium sulfate
7. distillationthe solvent was distilled off under reduced pressure
8. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate=99/1)
9. customto give Compound IIbk-a (19.4 g, 60.5%) as a white solid