反应详情

Combine p-toluenesulfonyl chloride (12.9 g, 67.4 mmol) in pyridine (15 mL) at room temperature and treat dropwise with 2,2-difluoroethanol (5.0 g, 60.9 mmol) via syringe. Stir the reaction mixture under nitrogen for 72 hours, partition between water (20 mL) and dichloromethane (20 mL). Separate the aqueous phase and extract with additional dichloromethane (2×40 mL). Combine the organic extracts and wash sequentially with 1 N hydrochloric acid (2×50 mL), sodium bicarbonate (2×50 mL), and brine (2×50 mL). Dry the organic layer over sodium sulfate and concentrate in vacuo to give the title compound as a yellowish oil: 1H NMR (300 MHz, CDCl3): 7.82 (d, 2H, J=9.0 Hz), 7.40 (d, 2H, J=9.0 Hz), 5.92 (tt, 1H, J=55.0, 0.4 Hz), 4.19 (td, 2H, J=12.6, 4.0 Hz), 2.48 (s, 3H).

1. custompartition between water (20 mL) and dichloromethane (20 mL)
2. customSeparate the aqueous phase
3. extractionextract with additional dichloromethane (2×40 mL)
4. washCombine the organic extracts and wash sequentially with 1 N hydrochloric acid (2×50 mL), sodium bicarbonate (2×50 mL), and brine (2×50 mL)
5. dry with materialDry the organic layer over sodium sulfate
6. concentrationconcentrate in vacuo