3, 5-Dihydroxypentyl benzene (3, 5-Dihydroxypentyl benzene) is mainly used as pharmaceutical intermediates in the pharmaceutical field. It naturally exists in various plants. In the early stage, 3, 5-dihydroxypentyl benzene was extracted by degrading plant lichens. More and more methods have been developed to prepare 3,5-dihydroxypentyl benzene.
We can take 3, 5-dihydroxybenzoic acid as raw material, after benzoyl hydroxylation, chlorinated with dichlorosulfoxide to get acyl chloride derivative, and then react acyl chloride with organic zinc reagent to get the corresponding ketone, and then reduce by hydrazine hydrate to get 3, 5-dihydroxybenzoic acid ester pentylene benzene. 3,5-dihydroxypentyl benzene can be obtained after water release and protection.
We can also use hexanal as raw material to obtain ethyl 2-octenate through Wittig reaction, which is added and condensed with ethyl acetoacetate to obtain sodium salt, and then react with cuprous bromide to obtain diketone bromide. 3,5-dihydroxypentyl benzene was obtained by debromination and decarboxylation of bromodione in DMF.
In addition, 3-nonene-2-ketone can be used as raw material for addition and condensation reaction with dimethyl malonate to obtain 3,5-dihydroxypentyl benzene in DMF. The product reacts with bromine for aromatization and decarboxylation.
There are various methods for preparing 3,5-dihydroxypentyl benzene, and the yield of 3,5-dihydroxypentyl benzene varies.