Influence of reaction conditions on product distribution in the green oxidation of cyclohexene to adipic acid with hydrogen peroxide

The effect of reaction conditions (such as the amount of sulfuric acid, reaction temperature and feeding style of reactants) on the product distribution in the green oxidation of cyclohexene to adipic acid was investigated. This reaction, with 30% hydrogen peroxide as oxidant in the presence of a homogeneous peroxy tungstate catalyst, is of great industrial interest for not using of organic solvent and phase-transfer catalyst. The synthesis we investigated produces adipic acid as the product, glutaric acid and succinic acid as main byproducts, and cyclohexanediol is an intermediate. Using this green method, a 94.5% yield of adipic acid has been achieved while byproducts and intermediates could be reduced. Finally, a proposed mechanism for the formation of glutaric acid was suggested, it was also supported by density functional theory calculations.

Under organic solvent- and phase-transfer catalyst-free conditions, the effect of reaction conditions on the product distribution in the green oxidation of cyclohexene to adipic acid with 30% hydrogen peroxide in the presence of a homogeneous peroxy tungstate catalyst has been investigated. A proposed mechanism for the generation of the main byproduct glutaric acid in this reaction has been suggested and studied using Gaussian 03 programme.Figure optionsDownload high-quality image (199 K)Download as PowerPoint slideHighlights
► Studying how reaction conditions change product distribution in this reaction.
► Firstly proposing a mechanism for the formation of glutaric acid in our system by DFT.
► Giving scientific basis for the industrialization of green synthesis of adipic acid.