反应详情

To a stirred solution of 4-methoxyphenyl methyl carbonate (5, 16.5 g. 91 mmol) in CH2Cl2 (205 mL) at 0° C. was added dropwise TiCl4(23.5 mL, 210 mmol) in CH2Cl2 (20 mL) over 30 min. Then MeOCHCl2 (9.3 mL, 104 mmol) in CH2Cl2 (20 mL) was added dropwise over 30 min. The reaction mixture was allowed to warm to room temperature and stirred for 30 min. The reaction material was poured into a mixture of ice (210 g) and concentrated HCl (8.5 mL). EtOAc (200 mL) was added and the mixture was stirred vigorously for 30 min. The aqueous layer was extracted with EtOAc (2×100 mL). The combined organic layers were dried (Na2SO4), filtered, and concentrated. The residue was recrystallized from EtOAc/hexanes to afford the title compound (16.6 g, 87%) as a light yellow solid: 1H NMR (500 MHz, CDCl3) δ 10.43 (s, 1H), 7.63 (d, J=3.1 Hz, 1H), 7.37 (dd, J=9.0, 3.1 Hz, 1H), 7.01 (d, J=9.0 Hz, 1H), 3.94 (s, 3H), 3.90 (s, 3H); ESI MS m/z 228 [M+H2O]+.

1. stirringthe mixture was stirred vigorously for 30 min
2. extractionThe aqueous layer was extracted with EtOAc (2×100 mL)
3. dry with materialThe combined organic layers were dried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was recrystallized from EtOAc/hexanes