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Abstract: The catalytic synthesis of ethylbenzene by alkylation of benzene with diethyl carbonate was carried out over HZSM-5 with Si/Al ratios from 50 to 250. The catalysts were characterized by XRD, SEM, 29Si and 27Al MAS-NMR, NH3-TPD and pyridine IR techniques. HZSM-5 with a Si/Al ratio of 200 exhibited the best benzene conversion and ethylbenzene selectivity because of its ideal acid strength. Strongly acidic sites may lead to an excessive decomposition of diethyl carbonate. The effects of temperature, feed ratio, WHSV and time-on-stream on catalytic activity and product selectivity were studied, and a possible mechanism is presented. [Copyright &y& Elsevier]

Readily-available triarylphosphines are explored as organocatalysts for the hydroarsination reaction. When compared to transition metal catalysis, phosphine organocatalysis greatly improved solvent compatibility of the hydroarsination of nitrostyrenes. Upon complete conversion, arsine products were isolated in up to 99% yield while up to 48% of the phosphine catalyst was still active. A mechanism was proposed and structure-activity analysis regarding catalyst activity concluded that sterically-bulkier catalysts were effective at minimizing catalyst deactivation. Image 1 • Air-stable triarylphosphine catalysts for the hydroarsination reaction. • Catalysis compatible with non-alcoholic solvents. • Arsine-mediated phosphine oxidation observed. • Organophosphine catalysis mechanistically different from transition metal catalysis. [ABSTRACT FROM AUTHOR]

The ruthenacyclic carbamoyl complexes [RuX{2‐NHC(O)C5H3NR}(CO)2(NCMe)] (R = H and Me; X = Br and SC6H3‐o,o‐Me2) are excellent catalysts for the hydrolysis of organosilanes, particularly towards primary silanes, generating hydrogen under ambient conditions within seconds. These complexes are structural mimics of the [Fe]‐hydrogenase active site and like the natural enzyme, a labile ligand at the sixth coordination site is essential to the catalytic activity. Complexes [RuX{2‐NHC(O)C5H3NR}(CO)2(NCMe)] (R = H and Me; X = Br and SC6H3‐o,o‐Me2) are excellent catalysts for the hydrolysis of organosilanes, particularly towards primary silanes, generating hydrogen under ambient conditions within seconds. These complexes are structural mimics of the [Fe]‐hydrogenase cofactor; a labile ligand at the sixth coordination site is essential to the catalytic activity. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "Asymmetric Synthesis of P-Stereogenic Diarylphosphinites by Palladium-catalyzed Enantioselective Addition of Diarylphosphines to Benzoquinone" by Y. Huang and colleagues published in "Journal of the American Chemical Society" in 2014.

The palladacycle-catalyzed asymmetric PH addition of 4- oxo-enamides has been developed, which provides efficient access to phosphinocarboxamides and their analogues. Solvent-mediated reversal of stereoselectivity ( ee from +96 % to −92 %) was observed, and the underlying mechanism that allows facile access to both enantiomers of the product by judicious choice of solvents is revealed. [ABSTRACT FROM AUTHOR]

Synthetic challenges have significantly slowed the development of the catalytic asymmetric hydroarsination reaction despite it being a highly attractive C−As bond formation methodology. In addition, there is a poor understanding of the main reaction steps in such reactions which limit further development in the field. Herein, key intermediates of the hydroarsination reaction catalyzed by a PCP NiII‐Cl pincer complex are presented upon investigating the reaction with DFT calculations, conductivity measurements, NMR spectroscopy, and catalytic screening. The novel Ni–Cl–As interaction proposed was then contrasted against known NiII‐catalyzed hydrophosphination reactions to highlight dissimilarities between them even though P and As share a close group relationship. Lastly, the asymmetric hydroarsination of nitroolefins was further developed to furnish a library of chiral organoarsines in up to 99 % yield and 80 % ee under mild conditions (−20 °C to RT) between 5 to 210 mins. [ABSTRACT FROM AUTHOR]

Bimetallic nanoparticles (NPs) are widely used in energy catalysis, chemical synthesis, and chemical/biosensing, but their performance at single NPs level is still needed to investigate. In this work, bimetallic Au@Pt/Au NPs with triple-layered core-shell structure was successfully prepared and characterized. The single bimetallic Au@Pt/Au NPs were immobilized on the surface of Au nanoelectrode through electrostatic adsorption. The results have showed that the single Au@Pt/Au NPs have size-dependent properties for voltametric response and electron-transfer rate, and exhibit excellent electrocatalytic activity, long-term tolerance and anti-toxicity compared with the traditional Pt catalyst. This work provides new insight into conventional electrocatalysis and will likely give a good platform for designing entirely new catalysts at single NPs level. [Display omitted] • The single bimetallic Au@Pt/Au NPs were immobilized on Au nanoelectrode through electrostatic adsorption. • Single Au@Pt/Au NPs have size-dependent properties for voltametric response and electron-transfer rate. • Single Au@Pt/Au NPs exhibit excellent electrocatalytic activity, long-term tolerance and anti-toxicity. [ABSTRACT FROM AUTHOR]

An abstract of the article "anti-Markovnikov Hydroimination of Terminal Alkynes in Gold-Catalyzed Pyridine Construction from Ammonia," by Liliang Wang and colleagues is presented.

The first catalytic asymmetric phospha-Michael addition of diphenylphosphine to 4-oxo-enamide using a palladacycle catalyst is developed. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "Polysubstituted Pyrrole Derivatives via 1,2-Alkenyl Migration of Novel γ-Amino-α,β-unsaturated Aldehydes and α-Diazocarbonyls" by S. Cal and colleagues published in the periodical "RSC Advances" in 2014.

The article presents chemical equations for Palladium-Catalyzed asymmetric intermolecular cyclization, published in the volume 52 of 2013 issue of the journal "Angewandte Chemie International Edition."

The article presents the steps of the chemical equations involved in the addition of diphenylphosphine to 3-methyl-4-nitro-5-alkenylisoxazoles.

A series of enantioenriched ferrocenyl monophosphines imbued with both central and planar chirality were obtained catalytically (80–99% ee) via the kinetic resolution of 1,2-disubstituted planar chiral ferrocenyl enone racemates. The synthetic approach utilized a chiral palladacycle to facilitate the asymmetric hydrophosphination (AHP) as a means to achieve high stereoselectivity. The enantioenriched ferrocenylphosphine products could be protected and further recrystallized to obtain ee s up to 99%. The modularity of the phosphine framework obtained was demonstrated via derivatization of its functional handles via a simple nucleophilic substitution to yield optically pure bisphosphines. Image 1 • Route towards ferrocenyl phosphines bearing both central and planar stereogenic elements. • Employs catalytic asymmetric P–H addition protocol to achieve efficient kinetic resolution. • Allows generation of 1,2 diphosphines from racemic substrates. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the chemical formula for organo-phosphorus compounds and the syntheses of chiral phosphino-carboxylic acid esters.

The facile phospha-Michael addition provides highly enantioenriched tertiary phosphine adducts. [ABSTRACT FROM AUTHOR]

The first protocol involving the catalytic enantioselective phospha-Michael addition of β,γ-unsaturated α-ketoesters and amides is presented. Synthetically important chiral tertiary phosphines are obtained with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]