反应详情

A mixture of 21.12 grams (0.07 mole) of ethyl 3-[(4-bromo-2-methylphenyl)amino]-3-oxopropanoate, 12.58 grams (0.11 mole) of N,N-dimethylformamide dimethyl acetal and 900 milliliters of cyclohexane was heated under reflux for a period of thirty two minutes at which time TLC indicated the reaction to be incomplete. Another 12.58-gram (0.11 mole) portion of the acetal was then added and the reaction mixture stirred overnight at ambient temperature. Solvent was stripped from the mixture under reduced pressure and the resulting solid then crystallized from hexane-ethyl acetate (10:1) to give 12.6 grams (0.035 mole) of ethyl 3-[(4-bromo-2-methylphenyl)amino]-2-(dimethylaminomethylene)-3-oxopropanoate having a melting point of 88° C.-90° C. Elemental analysis of the product indicated the following:

1. temperaturewas heated
2. temperatureunder reflux for a period of thirty two minutes at which time TLC
3. customthe reaction
4. customthe resulting solid then crystallized from hexane-ethyl acetate (10:1)