反应详情

To a solution of methyl 3,4-dihydroxy-5-methoxybenzoate (15.3 g, 0.0780 mol) in acetone (500 mL) was added CH2BrCl (34.4 g, 0.270 mol) and K2CO3 (75.0 g, 0.540 mol) at 80° C. The resulting mixture was heated at reflux for 4 h. The mixture was cooled to room temperature and solid K2CO3 was filtered off. The filtrate was concentrated under reduced pressure, and the residue was dissolved in EtOAc (100 mL). The organic layer washed with water, dried over anhydrous Na2SO4, and evaporated under reduced pressure to give the crude product, which was purified by column chromatography on silica gel (petroleum ether/ethyl acetate=10:1) to afford methyl 7-methoxybenzo[d][1,3]dioxole-5-carboxylate (12.6 g, 80%). 1H NMR (400 MHz, CDCl3) δ 7.32 (s, 1H), 7.21 (s, 1H), 6.05 (s, 2H), 3.93 (s, 3H), 3.88 (s, 3H).

1. temperatureThe resulting mixture was heated
2. temperatureat reflux for 4 h
3. filtrationsolid K2CO3 was filtered off
4. concentrationThe filtrate was concentrated under reduced pressure
5. dissolutionthe residue was dissolved in EtOAc (100 mL)
6. washThe organic layer washed with water
7. dry with materialdried over anhydrous Na2SO4
8. customevaporated under reduced pressure
9. customto give the crude product, which
10. customwas purified by column chromatography on silica gel (petroleum ether/ethyl acetate=10:1)