反応 #48214

反応方程式

benzoic acid 2-fluoro-5-methyl-phenyl ester

N-bromo-succinimide

dibenzoylperoxide

water

→

Benzoic Acid 5-bromomethyl-2-fluoro-phenyl Ester

溶媒

carbon tetrachloride

diethyl ether

反応条件

後処理

1. 1
   温度was heated
2. 2
   温度to reflux for 2 h (TLC monitored)
3. 3
   その他The organic layer was separated
4. 4
   洗浄washed with brine (20 mL)
5. 5
   乾燥dried over sodium sulphate
6. 6
   濃縮concentrated under reduced pressure
7. 7
   その他The residue was purified by column chromatography (EtOAc:hexane, 1:25, Rf: 0.28)

実験手順

A mixture of benzoic acid 2-fluoro-5-methyl-phenyl ester (CAB02145, 2.47 g, 10.0 mmol), N-bromo-succinimide (1.96 g, 11.0 mmol) and dibenzoylperoxide (10 mg) in carbon tetrachloride (25 mL) was heated to reflux for 2 h (TLC monitored). After cooling to room temperature, water (50 mL) and diethyl ether (100 mL) were added. The organic layer was separated, washed with brine (20 mL), dried over sodium sulphate and concentrated under reduced pressure. The residue was purified by column chromatography (EtOAc:hexane, 1:25, Rf: 0.28). Yield: 1.80 g (58%), white solid. 1H-NMR (400 MHz, CDCl3) δ=4.48 (s, 2H, —CH2Br), 7.18 (dd, J=9.8, 8.6 Hz, 1H), 7.28 (ddd, J=8.6, 4.3, 2.3 Hz, 1H), 7.34 (dd, J=7.0, 2.3 Hz, 1H), 7.50-7.55 (m, 2H), 7.64-7.69 (m, 1H), 8.18-8.23 (m, 2H). LRMS (FAB+): 229.1 (95), 309.0 (100, [M+]+). Found: C, 54.1, H, 3.22%; C14H10BrFO2 (309.13) requires C, 54.39, H, 3.26%.

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