Method of preparing floralozone intermediate

Abstract

The invention discloses a method of preparing a floralozone intermediate. Under the action of an aqueous sulfuric acid solution and a quaternary ammonium salt as a phase transfer catalyst, by controlling the reaction temperature, hydrogen chloride gas is continuously fed into a reaction system containing ethylbenzene and paraformaldehyde so as to perform chloromethylation of the ethylbenzene, and ethylbenzyl chloride with a purity higher than 95% and a yield being 85-94% is finally prepared. By adoption the ethylbenzyl chloride as the intermediate, floralozone can be prepared by condensing the intermediate and isobutyraldehyde.

Description

technical field [0001] The invention relates to a preparation method of an organic intermediate, in particular to a preparation method of a Haifeng aldehyde intermediate. Background technique [0002] The compounds that replace the phenylpropanal series have the fragrance of lily-of-the-valley, rabbit ear grass, and a fresh air style. It is named Haifeng aldehyde. Its fragrance is elegant and long-lasting, which can enhance the greenness of the essence formula and enhance the fragrance of green flowers. It has valuable use. value. [0003] Haifeng aldehyde can be obtained by condensation of ethyl benzyl halide with isobutyraldehyde under the action of a catalyst. It can be seen that ethyl benzyl halide as an organic synthesis intermediate is particularly important for the synthesis of Haifeng aldehyde. [0004] In the prior art, the synthesis of sea breeze aldehyde mostly adopts ethyl benzyl halide as the starting material, and the ethyl benzyl halide uses ethylbenzene and...

AI Technical Summary

Problems solved by technology

In this patent, not only the cost of raw materials used is relatively high, but also bromine needs to be recovered in the post-reaction treatment process, the process is cumbersome, and the "three wastes" are produced in a large amount

In "Chem Cat chem" 2010, No. 2, pages 392-396, it is described that aluminum trichloride, polyethylene glycol, etc. are used as catalysts to carry out the halomethylation reaction of aromatic hydrocarbons. The same catalysts cannot be reused, and the cost is relatively high. High, the amount of wastewater is large, which is not conducive to industrial production

[0006] As can be seen from the technical analysis of existing patents and documents, there are many problems in the existing ethylbenzene chloride / bromomethylation process, such as catalyst and post-treatment costs are higher, the catalyst cannot be recovered or recycled, and the yield is low. Moreover, the reaction produces more waste water, which is not conducive to environmental protection.