反应详情

A mixture of 3,5-dichloro-4-hydroxy benzoic acid methyl ester (5.525 g, 25 mmol), benzyl bromide (5.13 g, 30 mmol) and potassium carbonate (6.91 g, 50 mmol) in N,N-dimethylformamide (100 mL) was stirred overnight at room temperature. The reaction mixture was poured into crushed ice (ca. 300 g) and the product was extracted with ethyl acetate (2×100 mL). The combined organic layers were dried over sodium sulphate and concentrated under reduced pressure. The solid residue was recrystallised from ethyl acetate and hexane. Yield: 7.47 g (96%) fine white needles. 1H-NMR (400 MHz, CDCl3) δ=3.93 (s, 3H, —OCH3), 5.12 (s, 2H, —CH2Ph), 7.35-7.44 (m, 3H), 7.54-7.58 (m, 2H), 8.01 (s, 2H). 13C-NMR (100 MHz, CDCl3) δ=52.66, 75.12, 127.18, 128.41, 128.48, 129.79, 130.13, 135.57, 154.57, 164.39.

1. additionThe reaction mixture was poured
2. extractionthe product was extracted with ethyl acetate (2×100 mL)
3. dry with materialThe combined organic layers were dried over sodium sulphate
4. concentrationconcentrated under reduced pressure
5. customThe solid residue was recrystallised from ethyl acetate and hexane