Method for synthesizing 4-methyl-1, 2-phenylenedioxyacetic ester

Abstract

The invention discloses a method for synthesizing 4-methyl-1, 2-phenylenedioxyacetic ester, which comprises the following steps: taking 4-methylpyrocatechol and chloracetate as basic raw materials; taking aliphatic ketone or cyclic ketone as a solvent; performing heating reflux reaction for 6 to 10 hours in the presence of a phase transfer catalyst and anhydrous alkali metal carbonate; filtering after the cooling of the reaction; distilling a filtrate under reduced pressure after the solvent of the filtrate is recovered; and intercepting fractions of a product with the yield of between 85 and 98 percent. The method uses the chloracetate to realize the one-step etherification of the 4-methylpyrocatechol, has high yield and low cost, is particularly an environment-friendly method, and is easy to realize industrialized production.

Description

technical field [0001] The invention belongs to the synthesis technology of aromatic ring compounds with esters containing carbon, hydrogen and oxygen. Background technique [0002] Watermelon ketone has the aroma of fresh melon and watermelon, accompanied by a fresh ocean smell, the fragrance is transparent and long-lasting. Watermelon ketone can be prepared from 4-methylcatechol through etherification, condensation, hydrolysis and decarboxylation reactions [1] . [0003] [0004] The synthesis of the key intermediate 4-methyl-1,2-phenylenedioxyacetate has not been reported in patent literature. Only the synthesis method of 1,2-phenylene dioxyacetate [2] Can learn from. 1,2-Phenylenedioxyacetate can be obtained by reacting catechol with chloroacetonitrile or bromoacetate. [0005] [0006] The shortcoming of chloroacetonitrile route is that not only itself is poisonous but also has tear-stimulating effect, and synthetic route is long, need through etherification,...

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Problems solved by technology

[0006] The shortcoming of chloroacetonitrile route is that not only itself is poisonous but also has tear-stimulating effect, and synthetic route is long, need through etherification, hydrolysis, acidification and esterification four-step reaction, environment is unfriendly, reaction yield is lower, and cost is high; Bromine Although the acetate route only needs one-step reaction, because ethyl bromoacetate is not only toxic and has a strong lachrymatory effect, but also has a high price, this process also has the disadvantages of being environmentally unfriendly and high in cost.

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