反应详情

温度

45 °C

A mixture of methyl 3,5-bis(trifluoromethyl)benzeneacetate (Description 1, 10.0 g, 35 mmol), paraformaldehyde (1.15 g, 38.5 mmol) and sodium hydrogen carbonate (84 mg, 1 mmol) in dimethylsulfoxide (10 mL) was heated at 45° C. for 1 hour, cooled and water (200 mL) was added. The mixture was extracted with ether (2×200 mL) and the combined organic fractions were washed with water (4×100 mL) and brine (100 mL), dried (MgSO4) and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with isohexane/EtOAc (75:25) to give the title compound as a colorless oil (2.0 g, 10%). 1H NMR (400 MHz, CDCl3) δ 2.27 (1H, t, J 7.0 Hz), 3.76 (3H, s), 3.94–3.99 (2H, m), 4.01–4.15 (1H, m), 7.77 (2H, s) and 7.83 (1H, s).

1. temperaturecooled
2. extractionThe mixture was extracted with ether (2×200 mL)
3. washthe combined organic fractions were washed with water (4×100 mL) and brine (100 mL)
4. dry with materialdried (MgSO4)
5. customthe solvent was evaporated under reduced pressure
6. customThe residue was purified by flash column chromatography on silica gel
7. washeluting with isohexane/EtOAc (75:25)