反应详情

温度

0 °C

To a 250 mL round-bottomed flask was added chloroform (60 mL) along with 2,4-dimethoxybenzoic acid (2.0 g, 10.98 mmol). The solution was cooled to 0° C. and bromine (0.566 mL, 10.98 mmol) was added dropwise over 5 minutes. The solution was allowed to warm to room temperature and stirred overnight. The resulting solid was filtered, washed with cold chloroform and dried under vacuum to give 2.49 g (8.6 mmol, 78% yield) of 5-bromo-2,4-dimethoxybenzoic acid as a yellow solid. The LC/MS data was obtained on a Shimadzu analytical LC/MICROMASS® Platform LC (ESI+) at 220 nm using the following set of conditions: PHENOMENEX® Luna 3 μm C18, 2×30 mm column, with a gradient of 0-100% B (B=90% HPLC grade acetonitrile/0.1% trifluoroacetic acid/10% HPLC grade water), (A=90% HPLC grade water/0.1% trifluoroacetic acid/10% HPLC grade acetonitrile), in 2 minutes with a 1 minute hold at a rate of 1.0 mL/minute. 1H NMR (400 MHz, DMSO-d6) δ ppm 3.88 (s, 3H), 3.95 (s, 3H), 6.78 (s, 1H), 7.86 (s, 1H). LCMS Rt=1.453 min., m/z 262.99 (M+H), 93% purity.

1. temperatureto warm to room temperature
2. filtrationThe resulting solid was filtered
3. washwashed with cold chloroform
4. customdried under vacuum