反应详情

Under an argon atmosphere, zinc chloride (0.68 g, 4.97 mmol) was added to a 2.0 M solution of n-propyl magnesium chloride in diethyl ether (12.42 mL, 24.93 mmol), and the mixture was stirred at room temperature. After stirring for 0.5 hours, a solution of 2-bromo-3-chlorobenzaldehyde (4.36 g, 19.87 mmol), which had been obtained in Reference example 7 (7b), in tetrahydrofuran (10 mL) was added dropwise thereto. After stirring for 2 hours under ice cooling, a saturated aqueous ammonium chloride solution (20 mL) was added thereto. The mixture obtained was extracted with ethyl acetate (20 mL×2). After that, the organic layers were washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The residue was purified by silica gel chromatography (n-hexane/ethyl acetate=5/1) to give the title compound as a white solid (3.23 g, yield 62%).

1. stirringAfter stirring for 0.5 hours
2. additionwas added dropwise
3. stirringAfter stirring for 2 hours under ice cooling
4. customThe mixture obtained
5. extractionwas extracted with ethyl acetate (20 mL×2)
6. washAfter that, the organic layers were washed with saturated brine
7. dry with materialdried over anhydrous sodium sulfate
8. distillationThe solvent was distilled off under reduced pressure
9. customThe residue was purified by silica gel chromatography (n-hexane/ethyl acetate=5/1)