反应详情

To a solution of 3-bromo-4-cyanobenzoic acid (1.51 g, 6.69 mmol) in acetone (30 mL) was added cesium carbonate (4.4 g, 13.4 mmol) and benzyl bromide (790 uL, 6.69 mmol). The mixture was stirred at reflux for 15 hours at which point additional benzyl bromide was added (200 uL, 1.68 mmol). The mixture was stirred at reflux for a further 2 h and was then cooled to room temperature. Water and ethyl acetate were added and the layers were separated. The aqueous phase was then saturated with lithium chloride and extracted with ethyl acetate. The organic extracts were combined, dried over magnesium sulfate, filtered, and concentrated. The residue was purified by column chromatography (4:1 hexanes:ethyl acetate) to provide phenylmethyl 3-bromo-4-cyanobenzoate (957 mg, 3.03 mmol, 45% yield) as a yellow orange oil that slowly solidified. 1H NMR (400 MHz, CDCl3): 8.35 (d, 1H), 8.09 (dd, 1H), 7.73 (d, 1H), 7.46-7.35 (m, 5H), 5.35 (s, 2H).

1. additionwas added (200 uL, 1.68 mmol)
2. stirringThe mixture was stirred
3. temperatureat reflux for a further 2 h
4. customthe layers were separated
5. extractionsaturated with lithium chloride and extracted with ethyl acetate
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. customThe residue was purified by column chromatography (4:1 hexanes:ethyl acetate)