反应详情

温度

-78 °C

A stirred solution of 10 grams (0.061 mole) of ethyl phenylacetate in 125 mL of tetrahydrofuran is cooled to -78° C., and 33.5 mL (0.067 mole) of lithium diisopropylamide (2M solution in heptane-tetrahydrofuranethylbenzene) is slowly added dropwise at a rate to maintain the reaction mixture temperature below -60° C. Upon completion of addition, the reaction mixture is stirred at -78° C. for about one hour. After this time, 6.5 mL (0.067 mole) of ethyl acetate is added dropwise. Upon completion of addition, the reaction mixture is stirred for about one hour at -78° C. The reaction mixture is then allowed to warm to ambient temperature. After this time the reaction mixture is poured into 200 mL of water, and the mixture is extracted with one 100 mL portion of diethyl ether. The aqueous layer is made acidic with aqueous 10% hydrochloric acid, and then it is extracted with three 150 mL portions of diethyl ether. The combined extracts are dried with magnesium sulfate and filtered. The filtrate is concentrated under reduced pressure, yielding 6.6 grams of ethyl 3-oxo-2-phenylbutanoate. The NMR spectrum is consistent with the proposed structure.

1. temperatureto maintain the reaction mixture temperature below -60° C
2. additionUpon completion of addition
3. additionUpon completion of addition
4. stirringthe reaction mixture is stirred for about one hour at -78° C
5. temperatureto warm to ambient temperature
6. extractionthe mixture is extracted with one 100 mL portion of diethyl ether
7. extractionit is extracted with three 150 mL portions of diethyl ether
8. dry with materialThe combined extracts are dried with magnesium sulfate
9. filtrationfiltered
10. concentrationThe filtrate is concentrated under reduced pressure