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The fabrication of electrochemical biosensors without any binder or enzymes is in high demand in the clinical diagnostic and industrial sectors. This work presents the development of hydrogen-substituted graphdiyne encapsulated Cu2O nanowires (Cu2O NWs@ HsGDY) hybrid electrode, directly grown on Cu foils. The sp and sp2 hybridization of HsGDY is confirmed by Raman and X-ray photoelectron spectroscopy, and the HsGDY encapsulation over Cu2O NWs is observed in transmission electron microscope images. The fabricated binder-free, nonenzymatic electrode exhibits the highest sensitivity of 584.2 μA·cm2·μM–1 (Cu2O NWs@HsGDY-1 h), the lowest detection limits of 0.035 μM (Cu2O NWs@HsGDY-6 h) and a linear detection range of 0.5–2500 μM. The Cu2O NWs@HsGDY-6 h electrode demonstrates 70 days of stability (82%) and excellent reproducibility (RSD = 1.97%) compared to other hybrid electrodes. The improved glucose sensing performance and stability is a combined effect of semiconducting nature and catalytic ability are attributed to Cu2O NWs@HsGDY hybrid electrodes. The successful glucose detection in actual food samples indicates the practical applicability of the Cu2O NWs@HsGDY sensor. [ABSTRACT FROM AUTHOR]

The synthesis secondary amines, tertiary amines, and silyl enamines in the hydrosilane reduction of secondary amides catalyzed by a triruthenium complex is described.

Carbon‐nitrogen bond formation is an important method on both laboratory and industrial scales because it realizes the production of valuable pharmaceuticals, agrochemicals, and fine chemicals. Direct reductive N‐alkylation of amines with carbonyl compounds via intermediary imine compounds, especially under catalytic hydrogenation conditions, is one of the most convenient, economical, and environmentally friendly methods for this process. Here we report a novel palladium species on zirconia having specific activity towards hydrogenation of imines but other carbonyl groups remaining intact. The present catalytic property offers a practical synthetic method of functionalized secondary amines by reductive N‐alkylation under mild conditions with high atom‐efficiency. Mechanistic studies revealed that the catalytically active species is the palladium cluster, which is generated in situ from molecular palladium complexes on the support by exposure to atmospheric hydrogen. These fundamental findings are expected to progress in developing novel cluster catalysts for chemical processes directed towards a sustainable society. [ABSTRACT FROM AUTHOR]

A binaphthol-titanium complex (BINOL-Ti) catalyzed an asymmetric Diels-Alder (D.-A.) reaction in the absence of molecular sieves (MS). The MS-free complex demonstrated linear relationships with D.-A. products and the ee's of BINOC-Ti and exhibited stability at -20 degrees centigrade for several months.

The syntergetic effect of two Si-H groups which leads to efficient platinum-catalyzed reduction of carboxamides to amines under mild conditions is reported. The reduction of amides having other reducible functional groups such as N[O.sub.2], C[O.sub.2]R, CN, C-C, Cl, and Br moieties to provide a reliable method for the access to functionalized amine derivatives is also discussed.

An approach for a highly efficient synthesis of optically pure 5,5',6,6',7,7',8,8'-octahydro-1,1'-bi-2-naphthol and -naphthylamine derivatives is discussed. The production is obtained by the partial hydrogenation of various 1,1'-binaphthyls with carbon nanofiber supported ruthenium nanoparticles.

Combination of PdCl2 with 1,1,3,3‐tetramethyldisiloxane in the presence of activated carbon was found to be an effective catalyst system for the cleavage reaction of C−O bond of O−t‐Bu moieties. The present catalytic reaction offers a practical method for the deprotection of tert‐butyl esters, tert‐butyl ethers, O‐Boc, and N‐Boc derivatives under mild conditions. The addition of activated carbon in the reaction mixture was proved to be crucial for not only sustaining the catalytic activity but also trapping the palladium species after the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Palladium nanoparticles supported on 5 %‐nitrogen‐doped, herringbone‐type carbon nanofibers (Pd/N‐CNF‐H), which are prepared by thermally decomposing [Pd2(dba)3⋅CHCl3] (dba=dibenzylideneacetone) in toluene in the presence of N‐CNF‐H, were found to be an efficient catalyst for the chemoselective hydrogenation of alkenyl and nitro moieties in benzyl‐protected alcohols and carboxylic acid derivatives with high turnover frequencies: the hydrogenation reactions of these functional groups proceeded smoothly even at ambient temperature under atmospheric H2 pressure, and the benzyl protecting groups in the molecules remained intact. Moreover, the recovered Pd/N‐CNF‐H catalyst could be reused without loss of its catalytic activity or chemoselectivity. The Pd/N‐CNF‐H catalyst also acted as an effective hydrogenation catalyst for the reduction of aromatic ketones to the corresponding benzyl alcohol derivatives with good to high product selectivity. [ABSTRACT FROM AUTHOR]

The present reduction of amides with polymethylhydrosiloxane (PMHS) offers a solution as an environmentally benign production of amines, namely an efficient catalytic process involving facile separation of catalyst species and silicone byproducts from the product. The self-encapsulation of catalyst species into the silicone resin is considered to be one of the methods for microencapsulation of molecular catalysts into polymer supports.