反应详情

To a suspension of (methoxymethyl) triphenylphosphonium chloride (5.29 g, 14.9 mol) in Et2O (50 mL) was added 1.8 M phenyl lithium in 30% Et2O in cyclohexane (8.58 mL, 15.5 mmol). The mixture was stirred at ambient temperature for 10 min. To the reaction mixture was added 4-bromo-2-trifluoromethoxy-benzaldehyde (4 g, 14.9 mmol) in Et2O (18 mL). The mixture was stirred at ambient temperature for 4 hr, filtrated, and concentrated. To the above residue was added 10% H2SO4 in AcOH (40 mL). The mixture was stirred at ambient temperature for 90 min. The solution was poured into H2O, and the aqueous layer was extracted with CHCl3 (three times). The combined organic layer was washed with saturated aqueous NaHCO3, washed with brine, dried over MgSO4, filtered, concentrated, and purified by flash chromatography (silica gel, 9% EtOAc in hexane) to give (4-bromo-2-trifluoromethoxy-phenyl)-acetaldehyde (1.25 g, 30%) as a pale brown oil.

1. stirringThe mixture was stirred at ambient temperature for 4 hr
2. filtrationfiltrated
3. concentrationconcentrated
4. additionTo the above residue was added 10% H2SO4 in AcOH (40 mL)
5. stirringThe mixture was stirred at ambient temperature for 90 min
6. additionThe solution was poured into H2O
7. extractionthe aqueous layer was extracted with CHCl3 (three times)
8. washThe combined organic layer was washed with saturated aqueous NaHCO3
9. washwashed with brine
10. dry with materialdried over MgSO4
11. filtrationfiltered
12. concentrationconcentrated
13. custompurified by flash chromatography (silica gel, 9% EtOAc in hexane)