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In this work, we report a novel, one-step, inexpensive and environmentally friendly synthesis of Cu nanostructures by means of chemical de-alloying of bulk Cu–Ca alloys in aqueous solutions. By controlling the synthesis conditions, we tune the morphology of the nanostructured Cu from nanoporous Cu to copper oxide nanowires. [ABSTRACT FROM AUTHOR]

We report a novel wet chemistry route to metal coated nanodiamond particles. The technique includes adsorption of copper (II) acetate followed by reduction with hydrazine. To understand factors influencing the adsorption of the copper salt, nanodiamonds with different and well defined chemistries have been synthesized. The interaction of copper ions with NDs was studied by means of adsorption isotherms revealing different behavior depending on nanodiamond surface chemistry. Reduction of copper ions adsorbed on nanodiamond yields nanodiamond particles encapsulated into copper shells (ND@Cu). Using this technique, we can achieve up to 7.5 wt% of metallic copper on the nanodiamond surface, which is 3 times higher than reported so far. Synthesized copper coated nanodiamond particles will be used as a convenient nanofiller to reinforce copper and other metals with nanodiamond. [ABSTRACT FROM AUTHOR]

By sulfurization of phosphaalkenes ( a) either (σ3,λ5)-phosphoranes ( b) or (σ3,λ3)-thiaphosphiranes ( c) are formed. In this study, Density Functional Theory (DFT) and coupled cluster (CCSD(T)) calculations have been carried out for model and experimental structures of (σ3,λ5)-phosphoranes and (σ3,λ3)-thiaphosphiranes to elucidate the factors influencing relative stabilities of b and c. According to the results of quantum chemical calculations, sterically bulky substituents make the phosphorane form more favored. Conversely, electronic effects of the most substituents provide higher stability for thiaphosphirane isomers. The only exception has been found in the cases where the substituent at the phosphorus atom possesses π-donor and σ-acceptor properties (e.g., in the case of amino group) and the substituents at carbon atom exhibit σ-donor/π-acceptor effects (e.g., silyl groups). The stability of the cyclic form c decreases further, if the substituents at the carbon atom are amino groups. In this case, a quite unusual structure has been theoretically predicted, which is considerably different from those of the hitherto known phosphoranes. It indicates a pyramidal configuration at the phosphorus atom and can be conventionally presented as a donor-acceptor adduct of diaminocarbene with thioxophosphine. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Carbanion 4 generated from phosphane azide 3 undergoes intramolecular cyclization to give 1,2,3,4-triazaphosphole 5, which rearranges into 1,2,4-diazaphosphole 8. [ABSTRACT FROM AUTHOR]

This article summarizes some of our investigations of compounds featuring the structural fragment P-C-P. Phosphorus atoms in different oxidation states and coordination numbers display different chemical behaviors. This may lead to unique chemical properties when they are bridged by a methylene group in a P-CH2-P system. For example, the PIII-CH2-PVunit is able to add different unsaturated compounds to give zwitterionic products with oppositely charged phosphorus atoms. In addition, the two hydrogen atoms in P-CH2-P may also take part in different transformations, resulting in the formation of carbodiphosphoranes or in the formation of a direct P-P bond to give three-membered ring diphosphiranes. [ABSTRACT FROM AUTHOR]