反应详情

A mixture of 32.0 grams (0.126 mole) of ethyl 3-oxo-2-(2,5-dimethoxyphenylmethylidene)butanoate and 1.5 grams (catalyst) of 5% palladium on charcoal in 250 mL of ethyl acetate is hydrogenated using a Parr hydrogenation apparatus with hydrogen pressure at 20-40 psi. The hydrogenation requires about 12 hours. After this time, the reaction mixture is removed from the hydrogenator and filtered. The filtrate is concentrated under reduced pressure, yielding 32.2 grams of ethyl 3-oxo-2-(2,5-dimethoxy-phenylmethyl)butanoate. The NMR spectrum is consistent with the proposed structure.

1. customAfter this time, the reaction mixture is removed from the hydrogenator
2. filtrationfiltered
3. concentrationThe filtrate is concentrated under reduced pressure