In this work we present the successful application of functionalizing Pt nanoparticles (NPs) with hydrophilic organic ligands as a strategy for enhancing their catalytic activity and selectivity. first step, NPs were prepared by colloidal approach subsequently functionalized in separate synthesis step l-proline (PRO). The supported onto Al2O3 investigated heterogeneous catalysts selective hydrogenation acetophenone. Whereas significant amounts side products are formed supported,...

Significance Strong electrophilicity usually goes hand in with positive charge. In contrast, most negative ions behave like nucleophiles. Here we challenge this conventional wisdom by introducing an apparently counterintuitive idea that anions can, under well-defined circumstances, as superelectrophiles and even show superior binding strength kinetic product stabilization comparison typical superelectrophilic cations. Emanating from the stable gas-phase dianion [B 12 (CN) ] 2− , synthesized...

The perhalogenated closo-dodecaborate dianions [B12 X12 ](2-) (X=H, F, Cl, Br, I) are three-dimensional counterparts to the two-dimensional aromatics C6 X6 I). Whereas oxidation of parent compounds H12 and benzene does not lead isolable radicals, analogues can be oxidized by chemical or electrochemical methods give stable radicals. with strong oxidizer AsF5 in liquid sulfur dioxide (lSO2 ) yielded corresponding radical anions ](⋅-) (X=F, Br). presence ions was proven EPR UV/Vis spectroscopy...

The preparation of colloidal nanoparticles in alkaline ethylene glycol is a powerful approach for the model catalysts and ligand-functionalized nanoparticles. For these systems term "unprotected" has been established because no strongly binding stabilizers are required to achieve stable colloids. Irrespective this fact, particles must be considered as being covered by adsorbates, otherwise would coalesce precipitate. identification protecting adsorbate species however still under debate...

The stability and electron loss process of numerous multiply charged anions (MCAs) have been traditionally explained in terms the classical Coulomb interaction between spatially separated groups. An understanding these processes MCAs with not well-separated excess charges is still lacking. We report surprising properties physical behavior [B12X12]2–, X = F, Cl, Br, I, At, which are cannot be described by prevailing picture. In this series MCAs, comprising a "boron core" surrounded "halogen...

Abstract It is common and chemically intuitive to assign cations electrophilic anions nucleophilic reactivity, respectively. Herein, we demonstrate a striking violation of this concept: The anion [B 12 Cl 11 ] − spontaneously binds the noble gases (Ngs) xenon krypton at room temperature in reaction that typical “superelectrophilic” dications. Ng] adducts, with Ng binding energies 80 100 kJ mol −1 , contain B−Ng bonds substantial degree covalent interaction. nature confirmed spectroscopically...

Polyoxovanadate anions immobilized on conducting substrates are promising candidates for molecule-based memory technologies. However, strong electronic interactions with the substrate and formation of larger agglomerates remain bottlenecks way to their technical application. We demonstrate that ion soft-landing mass selected cyclodextrin-functionalized hexavanadates enables deposition these host–guest complexes as single units surfaces without quaternary ammonium countercations from...

Give Me strength: Methylation of the easily accessible weakly coordinating dianion [B12Cl12]2− affords Me2B12Cl12 (see picture). This neutral compound is a stronger methylating agent than commonly used methyl triflate, and it even methylates benzene. The synthesis, crystal structure, reactivity in solution gas phase are discussed. efficiency reagents strongly depends on properties anion. introduction carborane anions [CHB11R5X6]− (R=Me, Cl; X=Cl, Br) synthesis agents Me(CHB11Me5X6) (X=Cl, by...

Gas phase binding studies revealed strong intrinsic intermolecular interactions between dianionic dodecaborates [B₁₂X₁₂]²⁻ and neutral organic hosts.

The formation of traditional ionic materials occurs principally via joint accumulation both anions and cations. Herein, we describe a previously unreported phenomenon by which macroscopic liquid-like thin layers with tunable self-organization properties form through stable complex ions one polarity on surfaces. Using series highly molecular demonstrate strong influence the internal charge distribution ions, is usually shielded counterions, layers. Detailed characterization reveals that...

This Account highlights recent experimental and theoretical work focusing on the development of polyoxometalates (POMs) as possible active switching units in what may be called "molecule-based memory cells". Herein, we critically discuss how multiply charged vanadium-containing POMs, which exhibit stable metal-oxo bonds are characterized by excellent ability to change their redox states without significant structural distortions central polyoxoanion core, can immobilized best they optimally...

The gas phase reactivity of perhalogenated closo-dodecaborate clusters [B12X12]2− (X = F, Cl, Br, I) with N-tetraalkylated ammonium counter ions was investigated by electrospray ionization ion trap mass spectrometry (ESI-IT-MS). Collisions the background gases introduced a broad variety reactions. This study represents first experimental approach to new class boron-rich boron that are not accessible in condensed phase. anionic pair [B12X12 + N(CnH2n+1)4]− is generally found as highest mass....

A new apparatus for ion soft landing research was developed and is reported in this contribution. The instrument includes a dual polarity high-flux electrospray ionization (ESI) interface, tandem electrodynamic funnel system, collisional flatapole, quadrupole mass filter, focusing lens. enables production of ionic layers by mass-selected ions onto surfaces with balanced or imbalanced charge conditions using either layer-by-layer (LBL) fast switching modes. We present the first evidence...

High-yield syntheses up to molar scales for salts of [BH(CN)3 ]- (2) and [BH2 (CN)2 (3) starting from commercially available Na[BH4 ] (Na5), Na[BH3 (CN)] (Na4), BCl3 , (CH3 )3 SiCN, KCN were developed. Direct conversion Na5 into K2 was accomplished with SiCN SiCl as a catalyst in an autoclave. Alternatively, is converted Na[BH{OC(O)R}3 (R=alkyl) that more reactive towards thus provides easy access 2. Some reaction intermediates identified, example, Na[BH(CN){OC(O)Et}2 (Na7 b) Na[BH(CN)2...

Noble gas (Ng) containing molecular anions are much scarcer than Ng cations. No neon anion has been reported so far. Here, the experimental observation of [B12(CN)11Ne]- and a theoretical analysis boron-neon bond is reported.

We report the development of a new high-flux electrospray ionization-based instrument for soft landing mass-selected fragment ions onto surfaces. Collision-induced dissociation is performed in collision cell positioned after dual electrodynamic ion funnel assembly. The high duty cycle enables high-coverage deposition surfaces at defined kinetic energy. This capability facilitates investigation reactivity gaseous condensed phase. demonstrate that observed reactions deposited are dependent on...

Abstract The acidity of protic cations and neutral molecules has been studied extensively in the gas phase, gas‐phase established previously as a very useful measure intrinsic cationic compounds. However, no data for any anionic acids were available prior to this study. anions [H(B 12 X )] − (X=F, Cl, Br, I) are expected be most acidic known date. Therefore, they investigated study with respect their ability protonate phase by using combination mass spectrometry quantum‐chemical...

We report a joint benchmark study on the electronic stability of closo-dodecaborate [B12H12]2- employing negative ion photoelectron spectroscopy and high level structure methods. The spectra [B12H12]2-, measured at 266, 193, 157 nm, yield Adiabatic Vertical Detachment Energies (ADE VDE) this dianion 0.93 ± 0.05 eV 1.15 eV, respectively, along with ∼3 Repulsive Coulomb Barrier (RCB) against electron detachment. Theoretical calculations various levels theory confirm dianion. ADE VDE values...

While reactions between ions and neutral molecules in the gas phase have been studied extensively, molecular of same polarity remain relatively unexplored. Herein we show that fragment generated are possible by soft-landing both reagents on surfaces. The reactive [B12 I11 ]1- anion was deposited a surface layer built up landing generally unreactive I12 ]2- . Ex-situ analysis material shows [B24 I23 ]3- formed. A computational study product is metastable phase, but charge-balanced environment...

Abstract It has been shown by electrospray ionization–ion‐trap mass spectrometry that B 12 I 2− converts to an intact cluster as a result of successive stripping single iodine radicals or ions. Herein, the structure and stability all intermediate n − species ( =11 1) determined means first‐principles calculations are reported. The initial predominant loss radical occurs most probably via triplet state , reaction path for iodide ion from singlet crosses state. Experimentally, boron clusters...

Particle size alters activity but not stereoselectivity of ligand-functionalized nanoparticles suggesting that is primarily determined by the ligand–reactant combination.

Dependence of electronic properties and reactivity closo-borates with size halogen substituent was investigated.