反应详情

1-(3-bromo-4-fluorophenyl)ethanone (7.5 g, 34.5 mmol), ethylene glycol (10 mL) and a catalytic amount of tosyl acid was refluxed in toluene (100 mL) for 18 h with a Dean-Stark trap. The crude reaction mixture was quenched with H2O (100 mL) extracted with EtOAc (3×50 mL), washed organic layer with H2O, brine, dried (Na2SO4) and concentrated. The crude product was purified by flash chromatography (0 to 100% EtOAc/hexanes gradient) to afford 8.8 g of Intermediate 416.1. 1H NMR (400 MHz, CDCl3) δ ppm 1.61 (s, 3H) 3.69-3.81 (m, 2H) 3.97-4.09 (m, 2H) 7.07 (t, J=8.35 Hz, 1H) 7.32-7.43 (m, 1H) 7.67 (dd, J=6.59, 2.20 Hz, 1H).

1. customThe crude reaction mixture
2. customwas quenched with H2O (100 mL)
3. extractionextracted with EtOAc (3×50 mL)
4. washwashed organic layer with H2O, brine
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated
7. customThe crude product was purified by flash chromatography (0 to 100% EtOAc/hexanes gradient)