Preparation method of anisic aldehyde

Abstract

The invention discloses a preparation method of anisic aldehyde, and the method comprises the following steps of: S1, adding natural anise camphor and water into a bubbling reactor, introducing ozoneat 15-27DEG C to carry out ozone oxidation reaction for 200-300min, standing the reaction solution after the reaction is finished, carrying out phase splitting, and performing separation to remove thewater phase to obtain an organic phase for later use; S2, adding a reducing agent aqueous solution into the organic phase obtained in the S1, carrying out reduction reaction for 40-60min at the temperature of 70-80DEG C, and adding alkali liquor for neutralization so as to obtain an anisic aldehyde crude product; and S3, carrying out reduced pressure distillation on the anisic aldehyde crude product obtained in the S2, and collecting fractions with a pressure of 120-220Pa and a temperature of 120-170DEG C to obtain the anisic aldehyde finished product. The method is simple in process, mild inreaction condition, high in yield and high in raw material utilization rate, the total yield is 68-75%, the green and environment-friendly process requirements are met, and industrial production is facilitated.

Description

technical field [0001] The invention relates to the technical field of preparation methods of anisaldehyde, in particular to a preparation method of anisaldehyde. Background technique [0002] Anisaldehyde, also known as anisaldehyde, p-anisaldehyde, chemical name: 4-methoxybenzaldehyde, chemical structural formula:, chemical molecular formula: C 8 h 8 o 2 , molecular weight 136.15, colorless or light yellow liquid. Anisaldehyde is mainly used in the following aspects: 1. It is used to prepare flavors, which are allowed to be used in spices stipulated by GB2760-86 in my country. It is mainly used to prepare vanilla, spices, apricot, cream, fennel, caramel, cherry, chocolate , walnut, raspberry, strawberry, mint and other flavors; 2. Used as an important intermediate for the preparation of amoxicillin, antihistamine drugs, etc.; 3. Used as a brightener for electroplating metal; 4. As a color developer Track compounds with nitrogen functional groups. [0003] The methods cu...

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Problems solved by technology

[0004] 1. Traditional chemical oxidation method: This method uses potassium permanganate, manganese dioxide, sulfuric acid, etc. as oxidants. During the reaction process, a large amount of heavy metal salts such as chromium and manganese and a large amount of acid and alkali are consumed, and a large amount of manganese salt waste residue and chromium residue are produced. And waste water, there is the problem of "three wastes" pollution difficult to deal with, which causes great pollution to the environment, and the existence of acid will cause serious corrosion to production equipment at the same time, the yield of prepared anisaldehyde is only about 50%

[0005] 2. Electrochemical oxidation method: The electrochemical oxidation method uses graphite or titanium as the anode, stainless steel as the cathode, 80% to 90% ethanol aqueous solution as the solvent, and 0.25mol / L H 2 SO 4 As an electrolyte, the concentration of natural anethole is not more than 0.15mol / L, and the yield of anisaldehyde is about 60%. Compared with the traditional chemical oxidation method, the yield of anisaldehyde is greatly improved, but this method consumes a lot of electricity , and it is difficult to separate the products after the reaction, which is far from meeting the needs of industrial production

[0006] 3. Ozone oxidation method: Ozone oxidation method is a method that has been studied more in the past 30 years. Ozone has the characteristics of strong oxidizing power, better selectivity and faster reaction speed. Anethole is an unsaturated olefin with a benzene ring. Ozone can oxidize the double bond without attacking the benzene ring. However, a large amount of organic solvents are needed in the process of preparing anisaldehyde by the ozone oxidation method. On the one hand, there are high potential safety hazards in the ozone oxidation reaction, such as explosion accidents, and it is difficult to realize industrial production

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