Synthetic method of anethole

Abstract

The invention discloses a synthetic method of anethole. Anisole and propionyl chloride serve as starting raw materials, are subjected to a friedel-crafts acylation reaction, then are restored through sodium borohydride, and then are catalyzed and dehydrated through organic acid and acid inorganic salt, and finally the anethole is manufactured through rectification. Side reaction is low through the adoption of acylation and reduction, a middle body is not needed to be purified and can be directly put into the next reaction, purification loss and purification cost of the middle body are reduced, yield coefficient is improved, and energy consumption is reduced. A chemical reduction method is utilized to replace a catalytic hydrogenation method, selectivity is high, response speed is fast, side reactions are small in number, and reduction yield coefficient can reach above 98%. Double catalysts are adopted to carry out ordinary pressure low temperature dehydration in dissolvent with a low boiling point, and compared with a negative pressure continuous dehydration method, dehydration time can be shortened by 90%, and the energy consumption is greatly reduced. The total yield coefficient of the method can reach 75%. A product quality index is higher than that of a natural product standard.

Description

technical field [0001] The present invention relates to a kind of preparation method of fragrance compound, specifically relates to a kind of preparation method of anethole. Background technique [0002] Anethole (English name: Anethole), also known as anethole, anethole, p-propenylanisole, etc., is an aromatic compound widely present in nature, with the appearance of colorless or light yellow liquid or crystal, molecular formula C 10 h 12 O, the molecular weight is 148.2, the melting point is 22.5oC, the boiling point is 235oC, there are cis and trans isomers, the CAS number of the cis and trans anethole mixture is 104-46-1, and the trans anethole CAS number is 4180-23-8. Anethole is sweet and has a special aroma of fennel. Regardless of whether it is a natural product or a synthetic product, anethole exists in a mixed form of trans and cis, but the trans form is the main one. [0003] Anethole is favored by people because of its unique fennel smell, and is widely ...

AI Technical Summary

Problems solved by technology

[0007] (1) The side reaction of the acylation reaction is high, and the product must be separated and purified before it can be used for hydrogenation reduction, so the yield is low and the energy consumption is high;

[0008] (2) Although the cost of using hydrogen for the reduction reaction is low, but because there are many polymers, the product must be separated and purified before being used for the dehydration reaction, resulting in low yield and high energy consumption, and at the same time, the safety factor is reduced due to the pressurized reaction;

[0009] (3) The reaction time of negative pressure continuous dehydration is long, the requirements for vacuum, steam and other equipment working conditions are high, and the energy consumption is high;

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