Highly selective synthesis of primary amines over heterogeneous catalysts is still a challenge for the chemical industry. Ruthenium nanoparticles supported on NbO act as a highly selective and reusable heterogeneous catalyst for the low-temperature reductive amination of various carbonyl compounds that contain reduction-sensitive functional groups such as heterocycles and halogens with NH and H and prevent the formation of secondary amines and undesired hydrogenated byproducts. The selective catalysis of these materials is likely attributable to the weak electron-donating capability of Ru particles on the NbO surface. The combination of this catalyst and homogeneous Ru systems was used to synthesize 2,5-bis(aminomethyl)furan, a monomer for aramid production, from 5-(hydroxymethyl)furfural without a complex mixture of imine byproducts.

High-yielding one-pot synthesis of glucose from cellulose and pentoses/hexoses from real biomass is achieved by using simple activated carbons and 0.012% HCl in water. Ball-milling cellulose and the carbon together created good physical contact between the solid substrate and solid catalyst before the reaction, selectively and drastically improving the depolymerization rate of cellulose to oligomers. Thus, our methodology overcomes a major obstacle in this type of reaction, namely, that the collision between a solid catalyst and a solid substrate is limited. Mechanistic studies have suggested that the active sites of the carbons are weakly acidic functional groups, in which vicinal carboxylic and phenolic groups synergistically work for the hydrolysis reaction.

Cellulose is converted into sorbitol and related sugar compounds over water-tolerant and durable carbon-supported Pt catalysts under aqueous hydrogenation conditions. Pre-treatment of cellulose with ball-milling effectively reduces the crystallinity and particle size of cellulose, which results in 10 high conversion of cellulose to sorbitol and mannitol. The selectivity of sorbitol increases by using Cl-free metal precursors in the catalyst preparation as residual Cl on the catalysts promotes the side-reactions. The transformation of cellulose to sorbitol consists of the hydrolysis of cellulose to glucose via water-soluble oligosaccharides and the successive hydrogenation of glucose to sorbitol. The hydrolysis of cellulose is the rate-determining step, and the Pt catalysts promote both the 15 hydrolysis and the hydrogenation steps.

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A simple non-precious-metal catalyst system based on costeffective and ubiquitously available MnO , NaHCO , and molecular oxygen was used to convert 5-hydroxymethylfurfural (HMF) to 2,5-difurandicarboxylic acid (FDCA) as a bioplastics precursor in 91 % yield. The MnO catalyst could be recovered by simple filtration and reused several times. The present system was also applicable to the aerobic oxidation of other biomass-derived substrates and the gram-scale oxidation of HMF to FDCA, in which 2.36 g (86 % yield) of the analytically pure FDCA could be isolated.