反应详情

Lithium aluminum hydride (1.90 g) was suspended in tetrahydrofuran (200 ml) under a nitrogen atmosphere. A solution of 5-acetoxy-2,2-diisoamyl-4,6-di-tert-butyl-2,3-dihydrobenzofuran (17.4 g) in tetrahydrofuran (60 ml) was added dropwise to the suspension under cooling with ice. After heating under reflux overnight, the mixture was cooled to room temperature and water and a saturated aqueous solution of ammonium chloride were added in that order. The resulting insolubles were filtered off on Celite. The filtrate was subjected to extraction with diethyl ether, washed with saturated brine, dried over anhydrous magnesium sulfate and the solvent was distilled off. The residue was purified by silica gel chromatography (n-hexane) to afford 2,2-diisoamyl-4,6-di-tert-butyl-5-hydroxy-2,3-dihydrobenzofuran [9.0 g (yield, 57%)] as a colorless oil.

1. temperatureunder cooling with ice
2. temperatureAfter heating
3. temperatureunder reflux overnight
4. filtrationThe resulting insolubles were filtered off on Celite
5. extractionThe filtrate was subjected to extraction with diethyl ether
6. washwashed with saturated brine
7. dry with materialdried over anhydrous magnesium sulfate
8. distillationthe solvent was distilled off
9. customThe residue was purified by silica gel chromatography (n-hexane)