Research efforts to find more sustainable pathways for the synthesis of adipic acid have led to the introduction of new catalytic processes for producing this commodity chemical from alternative resources. With a focus on the performance of oxygen and hydrogen peroxide as preferred oxidants, this minireview summarizes recent advances made in the selective oxidation of cyclohexene, cyclohexane, cyclohexanone and n-hexane to adipic acid. Special attention is paid to the exploration of catalytic

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... thways involving lignocellulosic biomass-derived chemicals such as 5-hydroxymethylfurfural, D-glucose, g-valerolactone and compounds representative of lignin and lignin-derived bio-oils. Scheme 1 Simplified reaction scheme of the current industrial process for AA production by catalytic oxidation of KA oil with nitric acid. Scheme 6 Proposed mechanism for the transformation of cyclohexanone to e-caprolactone over HMSnP-1 in the presence of O 2 . 96 Scheme 7 Baeyer-Villiger oxidation of cyclohexanone with H 2 O 2 . Scheme 8 Hydrogenation of 5-hydroxymethylfurfural to 2,5-di-hydroxymethyltetrahydrofuran with RANEY s -Ni catalysts. 150 Scheme 10 Schematic illustration of the active sites on rhodium-rhenium catalysts for the hydrogenolysis of 2-THPM. Adapted from ref. 152. Scheme 9 Consecutive reaction pathway for the conversion of 2,5-di-hydroxymethyltetrahydrofuran to tetrahydro-2H-pyran-2-ylmethanol via 1,2,6-hexanetriol. 150