Preparation method of 2, 3, 5-trimethylhydroquinone diester

The invention relates to a method for preparing 2, 3, 5-trimethylhydroquinone diester from 3, 5, 5-trimethyl-cyclohex-2-ene-1, 4-diketone (oxoisophorone), and particularly relates to a method for preparing 2, 3, 5-trimethylhydroquinone diester from 3, 5, 5-trimethyl-cyclohex-2-ene-1, 4-diketone (oxoisophorone). According to the method, under the catalysis of a 3-hydroxy propanesulfonic acid modified silicon dioxide solid catalyst, oxoisophorone is subjected to a rearrangement reaction, and meanwhile, oxoisophorone and acid anhydride are subjected to an esterification reaction to prepare the 2, 3, 5-trimethylhydroquinone diester. In the reaction process, the peroxide value of reaction liquid is controlled to be smaller than 20, 2, 3, 5-trimethylhydroquinone diester with the chromaticity lower than 20 Hazen is prepared, the product purity is larger than 99.5%, the next-step reaction can be conducted without further purification, the catalyst can be recycled, generation of three wastes is reduced, and industrial