Ethyl 3-oxo-4-phenylbutanoate

Applications;

Ethyl 3-oxo-4-phenylbutanoate can be used to prepare pyrazolone derivatives as antipruritic compounds. It is also used to prepare pyrrolidine analogs as inhibitors of AP-1 and NF-κB-mediated gene expression.

Preparation;

(1) First, ethyl acetoacetate and dichloromethane of phenylacetyl chloride are mixed in a certain proportion. Then, the mixture and thionyl chloride are continuously pumped into a microchannel reactor at a certain flow rate using metering pumps, controlling the reactor outlet temperature to be 5–10℃. Next, the prepared saturated brine is continuously mixed with the reaction solution to form layers, with the reaction solution at the bottom and the brine at the top.

(2) Under normal pressure, the washed reaction solution is slowly heated. When the temperature at the bottom of the vessel reaches 55°C, dichloromethane begins to distill out. Heating continues until the vessel temperature reaches 100°C (ensuring complete solvent distillation). Heating is then stopped, and the distilled solvent is collected after cooling.

(3) After solvent recovery, vacuum distillation is performed under a vacuum of -0.1 MPa. The temperature is slowly increased. When the vessel temperature reaches 85–90°C, the reflux ratio is controlled at 4, and the finished product begins to distill out. When the vessel temperature reaches 120°C, heating is stopped, and the vacuum pump is turned off to obtain the qualified finished product Ethyl 3-oxo-4-phenylbutanoate. Its chromatographic content is then measured.