Phenylethyl acetate can be extracted from natural vegetable oils. Because phenylethyl acetate naturally exists in white orchid oil and rose oil, the composition is complex, and when it is extracted from natural vegetable oils, there is a problem that it is relatively difficult to separate.
It can also be synthesized by esterification. Phenylethyl acetate can be obtained by esterification reaction of acetic acid, acetic anhydride and phenylethyl alcohol in the presence of a catalyst.
Because the price of the raw material phenylethanol used in the synthesis of esterification is relatively high, the price of acetic anhydride is also high and the state control is very strict, while the price of acetic acid is relatively low, so the synthetic route of reaction between acetic acid and phenylethanol is mostly used in production. That is to use acetic acid and phenylethyl alcohol to heat and reflux for several hours under the action of a catalyst. After the reaction is completed, it is obtained by cooling, washing with water, neutralizing, washing with water until neutral, drying and distilling under reduced pressure. Because esterification is a reversible reaction and the yield is not high, it is usually used to increase the yield by using excess acetic acid in the reaction. After the reaction is completed, acidic wastewater will be generated, which is likely to cause environmental problems. It must be discharged after neutralization, and a large amount of waste water will be consumed. Alkali will cause waste of resources.
CN103553914A discloses a kind of synthetic method of phenylethyl acetate, is characterized in that comprising following process steps:
1>In the reaction kettle, add catalyst and ethyl acetoacetate, stir and heat to reflux, add benzyl chloride dropwise, and react under reflux for 2-6 hours to generate ethyl benzyl acetoacetate, evaporate the solvent and cool to room temperature, add water Stir to dissolve, add acid to adjust pH to 7, let stand to separate the layers, separate the oily substance in the lower layer, wash with water to obtain ethyl benzyl acetoacetate;
2> Add catalyst to the above product, reflux reaction for 2-6 hours, oily matter is formed, cool to below 30°C, add acid to adjust to PH = 1-2, continue heating and reflux for 1-4 hours, steam at normal pressure to remove low boiling Thing, obtains crude product benzyl acetone, distills under reduced pressure, obtains refined benzyl acetone;
3> Add refined benzyl acetone, m-chloroperoxybenzoic acid and solvent into the reaction kettle, react at room temperature for 2-6 hours, adjust the pH to 7 with alkali, separate the oil, wash with water, distill off the solvent, and refine acetic acid Phenylethyl ester, add acid to the water layer to adjust to PH = 1-2, crystallize, filter and recover m-chlorobenzoic acid, and the recovered m-chlorobenzoic acid is recycled.