Magnetically Induced Amination of Alcohols Using MNi@Cu (M=Fe, Co) Nanoparticles as Catalysts.

The synthesis of tertiary amines from alcohols (i.e. heptanol, dodecanol, cyclohexanol, benzylalcohol) and secondary amines (MeNH (DMA), PrNH, BuNH) has been achieved in one step using trimetallic nanoparticles (NPs) displaying a magnetic core (CoNi and FeNi) and a Cu shell as both catalysts and heating agent in the presence of an alternating magnetic field.

Correction: Supramolecular nanocapsules as two-fold stabilizers of outer-cavity sub-nanometric Ru NPs and inner-cavity ultra-small Ru clusters.

Correction for 'Supramolecular nanocapsules as two-fold stabilizers of outer-cavity sub-nanometric Ru NPs and inner-cavity ultra-small Ru clusters' by Ernest Ubasart , , 2022, , 607-615, https://doi.org/10.1039/D1NH00677K.

Induction heating: an efficient methodology for the synthesis of functional core-shell nanoparticles.

Induction heating has been applied for a variety of purposes over the years, including hyperthermia-induced cell death, industrial manufacturing, and heterogeneous catalysis. However, its potential in materials synthesis has not been extensively studied. Herein, we have demonstrated magnetic induction heating-assisted synthesis of core-shell nanoparticles starting from a magnetic core.

In situ Generated Iridium Nanoparticles as Hydride Donors in Photoredox-Catalyzed Hydrogen Isotope Exchange Reactions with Deuterium and Tritium Gas.

We have studied the photoredox-catalyzed hydrogen isotope exchange (HIE) reaction with deuterium or tritium gas as isotope sources and in situ formed transition metal nanoparticles as hydrogen atom transfer pre-catalysts. By this means we have found synergistic reactivities applying two different HIE mechanisms, namely photoredox-catalyzed and CH-functionalization HIE leading to the synthesis of highly deuterated complex molecules. Finally, we adopted these findings successfully to tritium chemistry.

Catalytic Sabatier Process under Thermally and Magnetically Induced Heating: A Comparative Case Study for Titania-Supported Nickel Catalyst.

In the present paper, we compare the activity, selectivity, and stability of a supported nickel catalyst in classical heating conditions and in magnetically activated catalysis by using iron wool as a heating agent. The catalyst, 5 wt% Ni supported on titania (Degussa P25), was prepared via an organometallic decomposition method and was thoroughly characterized by using elemental, microscopic, and diffraction techniques. In the event of magnetic induction heating, the % CO conversion reached a maximum of ~85% compared to ~78% for thermal conditions at a slightly lower temperature (~335 °C) than the thermal heating (380 °C).

Bringing Selectivity in H/D Exchange Reactions Catalyzed by Metal Nanoparticles through Modulation of the Metal and the Ligand Shell.

Ru and Rh nanoparticles catalyze the selective H/D exchange in phosphines using D as the deuterium source. The position of the deuterium incorporation is determined by the structure of the P-based substrates, while activity depends on the nature of the metal, the properties of the stabilizing agents, and the type of the substituent on phosphorus. The appropriate catalyst can thus be selected either for the exclusive H/D exchange in aromatic rings or also for alkyl substituents.

l-Lysine Stabilized FeNi Nanoparticles for the Catalytic Reduction of Biomass-Derived Substrates in Water Using Magnetic Induction.

The reduction of biomass-derived compounds gives access to valuable chemicals from renewable sources, circumventing the use of fossil feedstocks. Herein, we describe the use of iron-nickel magnetic nanoparticles for the reduction of biomass model compounds in aqueous media under magnetic induction. Nanoparticles with a hydrophobic ligand (FeNi -PA, PA=palmitic acid) have been employed successfully, and their catalytic performance is intended to improve by ligand exchange with lysine (FeNi -Lys and FeNi @Ni-Lys NPs) to enhance water dispersibility.

Water-soluble NHC Pd/Ni bimetallic nanoparticles for H/D exchange in aromatic amino-acids.

Labelling of amino-acids is important for the production of deuterated proteins. However, aromatic amino-acid reduction is a common undesired process with noble-metal nanocatalysts. In this work, we describe a new NHC-stabilized water-soluble Pd/Ni system able to perform H/D exchange reactions in an enantiospecific fashion without reducing the aromatic ring of phenylalanine and tyrosine thanks to a synergetic Pd-Ni effect.

CdP/ZnP Core-Shell Nanocrystals: Synthesis and Optical Properties.

II-V semiconductor nanocrystals such as CdP and ZnP have enormous potential as materials in next-generation optoelectronic devices requiring active optical properties across the visible and infrared range. To date, this potential has been unfulfilled due to their inherent instability with respect to air and moisture. Core-shell system CdP/ZnP is synthesized and studied from structural (morphology, crystallinity, shell diameter), chemical (composition of core, shell, and ligand sphere), and optical perspectives (absorbance, emission-steady state and time resolved, quantum yield, and air stability).

Magnetically Induced Catalytic Reduction of Biomass-Derived Oxygenated Compounds in Water.

The development of energetically efficient processes for the aqueous reduction of biomass-derived compounds into chemicals is key for the optimal transformation of biomass. Herein we report an early example of the reduction of biomass-derived oxygenated compounds in water by magnetically induced catalysis. Non-coated and carbon-coated core-shell magnetic nanoparticles were used as the heating agent and the catalyst simultaneously.

Organometallic Synthesis of Magnetic Metal Nanoparticles.

Magnetic nanoparticles (NPs) are attractive both for their fundamental properties and for their potential in a variety of applications ranging from nanomedicine and biology to micro/nanoelectronics and catalysis. While these fields are dominated by the use of iron oxides, reduced metal NPs are of interest since they display high magnetization and adjustable anisotropy according to their size, shape and composition. The use of organometallic precursors makes it possible to adjust the size, shape (sphere, cube, rod, wire, urchin, …) and composition (alloys, core-shell, composition gradient, dumbbell, …) of the resulting NPs and hence their magnetic properties.

Supramolecular nanocapsules as two-fold stabilizers of outer-cavity sub-nanometric Ru NPs and inner-cavity ultra-small Ru clusters.

The synthesis of metallic nanoparticles (MNP) with high surface area and controlled shape is of paramount importance to increase their catalytic performance. The detailed growing process of NP is mostly unknown and understanding the specific steps would pave the way for a rational synthesis of the desired MNP. Here we take advantage of the stabilization properties exerted by the tetragonal prismatic supramolecular nanocapsule 8·(BArF) to develop a synthetic methodology for sub-nanometric RuNP (0.

Commercial Cu Cr O Decorated with Iron Carbide Nanoparticles as a Multifunctional Catalyst for Magnetically Induced Continuous-Flow Hydrogenation of Aromatic Ketones.

Copper chromite is decorated with iron carbide nanoparticles, producing a magnetically activatable multifunctional catalytic system. This system (ICNPs@Cu Cr O ) can reduce aromatic ketones to aromatic alcohols when exposed to magnetic induction. Under magnetic excitation, the ICNPs generate locally confined hot spots, selectively activating the Cu Cr O surface while the global temperature remains low (≈80 °C).

A setup to measure the temperature-dependent heating power of magnetically heated nanoparticles up to high temperature.

Magnetic heating, namely, the use of heat released by magnetic nanoparticles (MNPs) excited with a high-frequency magnetic field, has so far been mainly used for biological applications. More recently, it has been shown that this heat can be used to catalyze chemical reactions, some of them occurring at temperatures up to 700 °C. The full exploitation of MNP heating properties requires the knowledge of the temperature dependence of their heating power up to high temperatures.

Determination of the surface temperature of magnetically heated nanoparticles using a catalytic approach.

Herein we describe a new method for the determination of the surface temperature of magnetically heated nanoparticles in solution using the temperature dependency of the catalytic performances of iron carbide nanoparticles coated with ruthenium (FeC@Ru) for acetophenone hydrodeoxygenation. A correlation between nanoparticle surface temperature and magnetic field could be established. Very high surface temperatures could be estimated in different solvents, which were also found similar at a given magnetic field and well above some solvent boiling points.

A combined theoretical/experimental study highlighting the formation of carbides on Ru nanoparticles during CO hydrogenation.

Formation of stable carbides during CO bond dissociation on small ruthenium nanoparticles (RuNPs) is demonstrated, both by means of DFT calculations and by solid state C NMR techniques. Theoretical calculations of chemical shifts in several model clusters are employed in order to secure experimental spectroscopic assignations for surface ruthenium carbides. Mechanistic DFT investigations, carried out on a realistic Ru nanoparticle model (∼1 nm) in terms of size, structure and surface composition, reveal that ruthenium carbides are obtained during CO hydrogenation.

Bimetallic Nanoparticles Associating Noble Metals and First-Row Transition Metals in Catalysis.

Bimetallic nanoparticles (NPs) are complex systems with properties that far exceed those of the individual constituents. In particular, association of a noble metal and a first-row transition metal are attracting increasing interest for applications in catalysis, electrocatalysis, and magnetism, among others. Such objects display a rich structural chemistry thanks to their ability to form intermetallic phases, random alloys, or core-shell species.

Nanocatalyzed Hydrogen Isotope Exchange.

Recently, hydrogen isotope exchange (HIE) reactions have experienced impressive development due to the growing importance of isotope containing compounds in various fields including materials and life sciences, in addition to their classical use for mechanistic studies in chemistry and biology. Tritium-labeled compounds are also of crucial interest to study the fate of a bioactive substance or in radioligand binding assays. Over the past few years, deuterium-labeled drugs have been extensively studied for the improvement of ADME (absorption, distribution, metabolism, excretion) properties of existing bioactive molecules as a consequence of the primary kinetic isotope effect.

Organometallic Synthesis of Bimetallic Cobalt-Rhodium Nanoparticles in Supported Ionic Liquid Phases (Co Rh @SILP) as Catalysts for the Selective Hydrogenation of Multifunctional Aromatic Substrates.

The synthesis, characterization, and catalytic properties of bimetallic cobalt-rhodium nanoparticles of defined Co:Rh ratios immobilized in an imidazolium-based supported ionic liquid phase (Co Rh @SILP) are described. Following an organometallic approach, precise control of the Co:Rh ratios is accomplished. Electron microscopy and X-ray absorption spectroscopy confirm the formation of small, well-dispersed, and homogeneously alloyed zero-valent bimetallic nanoparticles in all investigated materials.

Ultrastable Magnetic Nanoparticles Encapsulated in Carbon for Magnetically Induced Catalysis.

Magnetically induced catalysis using magnetic nanoparticles (MagNPs) as heating agents is a new efficient method to perform reactions at high temperatures. However, the main limitation is the lack of stability of the catalysts operating in such harsh conditions. Normally, above 500 °C, significant sintering of MagNPs takes place.

Tuning the Reactivity of a Heterogeneous Catalyst using N-Heterocyclic Carbene Ligands for C-H Activation Reactions.

We report the dramatic impact of the addition of N-heterocyclic carbenes (NHCs) on the reactivity and selectivity of heterogeneous Ru catalysts in the context of C-H activation reactions. Using a simple and robust method, we prepared a series of new air-stable catalysts starting from commercially available Ru on carbon (Ru/C) and differently substituted NHCs. Associated with C-H deuteration processes, depending on Ru/C-NHC ratios, the chemical outcome can be controlled to a large extent.