反应详情

Using the procedure in Example 85, step (b), the entire sample of 3-(chlorocarbonyl)-6-methoxyphenyl acetate (as prepared in the previous step) in 5 mL of anhyd CH2Cl2 was treated with 2.09 mL (4.18 mmol) of a 2 M solution of trimethylsilyldiazomethane in hexane and 456 μL (2.28 mmol) of 30 wt % HBr in acetic acid. Chromatography as in Example 85, step (b) followed by recrystallization from CH2Cl2-hexane afforded the title compound as a faintly yellow solid (366 mg, 67%). 1H-NMR (300 MHz, CDCl3) δ7.79 (dd, 1H, J=8.6, 2.2 Hz), 7.70 (d, 1H, 2.2 Hz), 7.03 (d, 1H, 8.6 Hz), 4.38 (s, 2H), 3.92 (s, 3H), and 2.34 (s, 3H).

1. customChromatography as in Example 85, step (b) followed by recrystallization from CH2Cl2-hexane