Synthetic preparation method of wintergreen oil

Abstract

The invention relates to the field of chemical synthesis, and particularly discloses a synthetic preparation method of wintergreen oil. The synthetic preparation method comprises the following steps:(1) methanol, salicylic acid and methyl carboxylate are sequentially put into a reaction kettle according to the molar ratio of (2 to 3):1:(0.1 to 0.3); (2) a synthetic reaction is generated under theconditions of heating and pressurization, and a mixed solution A containing the wintergreen oil is obtained; and (3) the mixed solution A is distilled and separated to obtain the wintergreen oil. According to the method, the defects of a traditional concentrated sulfuric acid catalytic method are overcome, and the methyl carboxylate serves as a catalyst, so that the beneficial effects that raw materials are easy to obtain, the reaction flow is simple, the catalyst can be removed only through simple distillation, subsequent treatment is easy, and the prepared wintergreen oil is large in product purity and high in conversion rate are achieved.

Description

technical field [0001] The invention belongs to the field of chemical synthesis, and in particular relates to a synthetic preparation method of wintergreen oil. Background technique [0002] Wintergreen oil has a wintergreen aroma and is also known as Methyl Salicylate. It exists widely in nature and is the main component of wintergreen and Xiaodang medicinal oil. It is now widely used as a solvent, preservative, and fixative in fine chemical industry, and also as a spice for beverages, food, toothpaste, cosmetics, etc., as well as for the production of analgesics, insecticides, polishes, inks, and Fiber dyeing aids, etc., and its anti-inflammatory, analgesic, bactericidal effects and ability to penetrate the skin are widely used in the pharmaceutical industry. [0003] The traditional synthetic method of wintergreen oil is mainly esterification. This method takes salicylic acid and methanol as raw materials, and carries out esterification synthesis reaction under the cata...

AI Technical Summary

Problems solved by technology

Although this method overcomes some defects of the traditional concentrated sulfuric acid catalytic method, it still has the disadvantages of using p-toluenesulfonic acid as a catalyst, which is expensive and difficult to recycle; Preparation process of methyl salicylate", the preparation process adopts sol-gel technology to prepare TiO2 composite photocatalyst, instead of traditional concentrated sulfuric acid catalyst

Although this process overcomes some defects of the traditional concentrated sulfuric acid catalysis method, there are disadvantages such as the use of TiO2 composite photocatalyst, the preparation process of the catalyst is complicated, the whole synthesis reaction is complicated, the practicability is poor, and the follow-up treatment of the reaction is complicated; another example: Publication No. The patent name of CN105622403A is "a method for the synthesis and preparation of high-quality methyl salicylate". The synthesis method uses a new catalyst to replace the original concentrated sulfuric acid catalyst. and additives, wherein the base material is silicon dioxide, diatomaceous earth and aluminum oxide, and the polysaccharide is one or more of polyacetylglucosamine, galactose and polyfructose, and the sulfide It is one or both of potassium hydrogen sulfate and copper sulfate, and the auxiliary agent is one or both of polyvinyl alcohol and polysorbate

Although this synthesis method overcomes some defects of the traditional concentrated sulfuric acid catalytic method, there are still shortcomings such as complex preparation process of the catalyst, poor practicability, and complicated post-reaction treatment.