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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]

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]

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]