反应详情

Pentyltriphenylphosphonium bromide (1.17 g, 2.83 mmol) and ether (5 ml) were mixed, and to this solution was added a hexane solution (1.6M, 1.77 ml) of n-butyllithium (2.83 mmol). The mixture was stirred at room temperature for 2 hours. A THF solution (3 ml) of 5-(4,4-dimethyl-4,5-dihydrooxazol-2-yl)-2-methoxybenzaldehyde (600.8 mg, 2.58 mmol) was added to this solution, and the mixture was stirred for 1.5 hours. Water (5 ml) was added to stop the reaction. The aqueous layer was extracted 3 times with ethyl acetate (5 ml). The organic layers were combined, and washed twice with saturated brine (20 ml1). This solution was dried over anhydrous magnesium sulfate, and the drying agent was filtered off. The filtrate was concentrated under reduced pressure, and the obtained residue was purified by column chromatography (hexane/ethyl acetate=2/1) to give 2-[3-(1-hexenyl)-4-methoxyphenyl]-4,4-dimethyl-4,5-dihydrooxazole (583.3 mg, 79%) as a mixture (a colorless oil) of geometrical isomers (1:1).

1. stirringthe mixture was stirred for 1.5 hours
2. customthe reaction
3. extractionThe aqueous layer was extracted 3 times with ethyl acetate (5 ml)
4. washwashed twice with saturated brine (20 ml1)
5. dry with materialThis solution was dried over anhydrous magnesium sulfate
6. filtrationthe drying agent was filtered off
7. concentrationThe filtrate was concentrated under reduced pressure
8. customthe obtained residue was purified by column chromatography (hexane/ethyl acetate=2/1)