反应详情

A solution of 31.9 mL (0.25 mole) of ethyl acetoacetate is stirred in hexane (350 mL) at room temperature. Triethylamine (42 mL, 0.30 mole) is added, followed by dropwise addition of trimethylsilyl chloride (35 mL, 0.276 mole) keeping the internal temperature below 25° C. using a water bath (about 18° C.). The thick white slurry is stirred overnight at room temperature. 200 mL of hexane is then added and the mixture stirred in an ice bath for 1 hour. The mixture is filtered and the solids are washed with 50 mL of cold hexane. Evaporation of the combined filtrate and washings gives 46 g of 3-trimethylsilanyloxy-but-2-enoic acid ethyl ester as a colorless, slightly cloudy oil. This material is used without further purification in the following step.

1. customthe internal temperature below 25° C.
2. custom(about 18° C.)
3. stirringthe mixture stirred in an ice bath for 1 hour
4. filtrationThe mixture is filtered
5. washthe solids are washed with 50 mL of cold hexane
6. customEvaporation of the combined filtrate and washings