反应详情

A pentane solution (6.0 ml) of 1.6M n-butyllithium was added dropwise to a solution of n-heptyltriphenylphosphonium bromide (4.2 g) in tetrahydrofuran (30 ml) under a nitrogen atmosphere. After stirring the mixture at room temperature for 90 min, a solution of 5-acetoxy-4,6-di-tert-butyl-2-formylbenzofuran (2.54 g) in tetrahydrofuran (20 ml) was added dropwise. Subsequently, the mixture was heated under reflux for 1 h and, after cooling, a saturated aqueous solution of ammonium chloride was added and the mixture was subjected to extraction with 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-(1-octenyl)benzofuran [3.1 g (yield, 97%)] as a colorless oil.

1. temperatureSubsequently, the mixture was heated
2. temperatureunder reflux for 1 h
3. temperatureafter cooling
4. extractionthe mixture was subjected to extraction with 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)