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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.

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.

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.

The H-shape alkanes of various arm lengths have been synthesized successfully through the Grignard reaction. The detailed investigation of these novel compounds may allow us to widen the topological chemistry field furthermore. The molecular form and molecular packing structure in the crystal lattice have been revealed successfully on the basis of X-ray structure analysis as well as the analysis of Raman longitudinal acoustic modes (LAM) sensitive to the alkyl zigzag chain segments. The molecular conformation in the crystal lattice is deformed markedly from the originally imagined H-shape. In the cases of C3HOH to C6HOH, for example, the molecules are packed in a complicated manner and the OH···O hydrogen bonds govern the whole intermolecular interactions mainly. Since the alkyl segmental length is not very long, the conformational change is not very drastic, i.e., the small configurational entropy. Synergic effect of the hydrogen bonds and the small configurational entropy gives the higher melting point as known from the thermal data. On the other hand, in the cases of C10HOH and C12HOH, one of the long alkyl chain arms is found to be bent by 90° so that all of the alky chain segments of planar-zigzag conformation can be packed as closely as possible, and the intermolecular OH···O hydrogen bonds are also formed effectively without any mistake. As a result, the contribution of nonbonded intra- and intermolecular van der Waals interactions between the trans-zigzag alkyl chain segments become major, and the coupling of this enthalpy effect with the larger configurational entropy effect of the molecular shape results in the decrement of the melting point which approaches gradually that of longer n-alkane compound. In this way a sensitive balance between the nonbonded van der Waals interactions, the OH···O hydrogen bonds, as well as the configurational entropy effect gives the characteristic thermal behavior of the H-shape compounds. The thus-newly synthesized H-shape alkane compounds should give us new insight into the packing topology of complicated molecules, leading to the development of new functionality unexpected for normal linear alkane compounds., (© 2011 American Chemical Society)

Rhodium nanoparticles supported on a carbon nanofiber (Rh/CNF-T) show high catalytic activity toward arene hydrogenation under mild conditions in high turnover numbers without leaching the Rh species; the reaction is highly tolerant to epoxido groups, which often undergo ring-opening hydrogenation with conventional catalysts.

Novel polysiloxane gels, to which platinum species are encapsulated, are prepared by treatment of polymethylhydrosiloxane with alkenes in the presence of Karstedt's catalyst. These gels act as reusable catalysts in the reduction of functionalized nitroarenes with H(2) to the corresponding substituted anilines without leaking the catalyst species.

Platinum and palladium nanoparticles supported on three types of carbon nanofibers (CNFs) are synthesized and used as catalysts in the hydrogenation of nitroarenes. Nanosized platinum particles dispersed on platelet-type CNF efficiently catalyze the reduction of functionalized nitroarenes to the corresponding substituted anilines in high turnover numbers with other functional groups remaining intact.