反应详情

A mixture of 7-bromo-2,2,4,6-tetramethyl-1-benzofuran-3(2H)-one (2.90 g, 10.8 mmol) synthesized in Reference Example 67, copper bromide (1.86 g, 13.0 mmol) and 28% sodium methoxide/methanol solution (60 mL) was stirred under heated reflux for 15 hours. After cooled to room temperature, the reaction solution was poured into water and extracted using ethyl acetate. The extract was washed with saturated saline, and dried using anhydrous magnesium sulfate. After that, the solvent was removed under reduced pressure. The residue was purified by silica gel column chromatography (hexane-ethyl acetate 99:1 to 94:6) to give 1.18 g of the title compound (yield: 50%).

1. temperatureunder heated
2. temperaturereflux for 15 hours
3. extractionextracted
4. washThe extract was washed with saturated saline
5. customdried
6. customAfter that, the solvent was removed under reduced pressure
7. customThe residue was purified by silica gel column chromatography (hexane-ethyl acetate 99:1 to 94:6)