反应详情

Phosphorus oxychloride (1.1 g) was added dropwise to N,N-dimethylformamide (0.4 g) under cooling with ice and, subsequently, a solution of 5-acetoxy-4,6-di-tertbutylbenzofuran (1.0 g) in N,N-dimethylformamide (2 ml) was added dropwise. The mixture was stirred first at room temperature for 20 min, then under heating at 80° C. for 75 min. After cooling, the reaction mixture was poured into water and subjected to extraction ethyl acetate. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate and concentrated. The concentrate was purified by silica gel chromatography (10% ethyl acetate in n-hexane) to afford 5-acetoxy-4,6-di-tert-butyl-2-formylbenzofuran [0.95 g (yield, 86%)] as a colorless, fine-grained crystal.

1. temperatureunder cooling with ice
2. temperatureunder heating at 80° C. for 75 min
3. temperatureAfter cooling
4. extractionsubjected to extraction ethyl acetate
5. washThe organic layer was washed with water and saturated brine
6. dry with materialdried over anhydrous magnesium sulfate
7. concentrationconcentrated
8. customThe concentrate was purified by silica gel chromatography (10% ethyl acetate in n-hexane)