Shift happens: Concerns about the depletion of fossil fuel reserves and the environmental problems related to its use have encouraged the development of new catalytic approaches for producing carbon‐based chemicals from cellulosic biomass. Here, recent progress in the implementation of (mainly) heterogeneous acid, bifunctional, and multistep catalysis is reviewed.

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 pathways 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

Heterogeneous catalysis offers a sustainable toolbox for the synthesis of a wide variety of biomass-derived amines.

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Hf-, Zr- and Sn-Beta zeolites effectively catalyze the coupled transfer hydrogenation and etherification of 5-(hydroxymethyl)furfural with primary and secondary alcohols into 2,5-bis(alkoxymethyl)furans, thus making it possible to generate renewable fuel additives without the use of external hydrogen sources or precious metals. Continuous flow experiments reveal nonuniform changes in the relative deactivation rates of the transfer hydrogenation and etherification reactions, which impact the observed product distribution over time. We found that the catalysts undergo a drastic deactivation for the etherification step while maintaining catalytic activity for the transfer hydrogenation step. (119) Sn and (29) Si magic angle spinning (MAS) NMR studies show that this deactivation can be attributed to changes in the local environment of the metal sites. Additional insights were gained by studying effects of various alcohols and water concentration on the catalytic reactivity.