Method for preparing N-ethyl-2-isopropyl-5-methycyclohexane

Abstract

The invention discloses a method for preparing N-ethyl-2-isopropyl-5-methycyclohexane, and belongs to the technical field of amide preparation. The method comprises the following steps: using mint alkyl chloride as a raw material and ethyl bromide as an initiator to firstly prepare chlorinated mint alkyl magnesium; then using trichloromethyl carbonate to prepare mint acyl chloride; and finally obtaining the N-ethyl-2-isopropyl-5-methycyclohexane through the aminolysis reaction of the mint acyl chloride and mono ethyl amine. The method has the advantages of simplicity, simple and convenient operation, mild reaction condition and low production cost; the yield of a product can reach about 80 percent; and the purity of the product reaches more than 99.2 percent. The product prepared by the method has intense cooling flavor effect and long taste retention time, and can be widely applied in the industries of food, medicine, cosmetics, tobacco, and the like.

Description

technical field [0001] The invention belongs to the technical field of amide preparation, in particular to a preparation method of N-ethyl-2-isopropyl-5-methylcyclohexanecarboxamide. technical background [0002] Studies have shown that: menthol amide has a strong cooling effect, long-lasting cooling effect, no bitterness, mild skin feeling, no irritation, no burning feeling, obvious flavoring effect, and can be used well with any cooling agent It can be used in food, medicine, daily chemical, tobacco and other industries, but because of its high price, its scope of application is limited, so the research on the synthesis of menthamide has important economic and social value. [0003] An existing method for preparing N-ethyl-2-isopropyl-5-methylcyclohexanecarboxamide is to start from menthyl chloride and prepare it through steps such as Grignard reaction, acidification, acyl chloride and amidation product. For example, the patent of "High Efficiency Refrigerant--Preparatio...

AI Technical Summary

Problems solved by technology

For example, the patent of "High Efficiency Refrigerant--Preparation Method of Amidated Natural Menthol" with publication number CN1613845 discloses the preparation of amide from menthol through processes such as chlorination, Grignard reaction, acidification, acyl chloride, amidation, and recrystallization. Natural menthol; The disadvantage of this method is that the reaction conditions are strict in the acidification step, and the yield is low

For example, in the article "Synthesis of cooling agent N-ethyl-L-menthyl formamide" in the 11th issue of Fine Chemical Industry in November 2008, it is introduced that menthol is chlorinated, cyanated, and then the product is obtained through Ritter reaction; The disadvantage of this method is that during the cyanation process, menthyl chloride reacts with sodium cyanide as an intermediate to generate menthyl cyanide. The reaction yield is extremely low, and sodium cyanide is a highly toxic substance, which increases the difficulty of production operations.