A5017749564- Catalytic Processes in Materials Science
- Fluorine in Organic Chemistry
- Inorganic Fluorides and Related Compounds
- Chemical Synthesis and Characterization
- Catalysis and Oxidation Reactions
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Organoboron and organosilicon chemistry
- Catalysts for Methane Reforming
- Synthesis and characterization of novel inorganic/organometallic compounds
- Carbon dioxide utilization in catalysis
- Electrocatalysts for Energy Conversion
- Ammonia Synthesis and Nitrogen Reduction
- Catalytic Cross-Coupling Reactions
- CO2 Reduction Techniques and Catalysts
- Advanced Materials Characterization Techniques
- Cyclopropane Reaction Mechanisms
- Asymmetric Hydrogenation and Catalysis
- Methane Hydrates and Related Phenomena
- Fluoride Effects and Removal
- Innovative Microfluidic and Catalytic Techniques Innovation
- Radical Photochemical Reactions
- Nanomaterials for catalytic reactions
University of Oxford
2023-2025
Scripps Research Institute
2024
Eindhoven University of Technology
2020-2022
All fluorochemicals—including elemental fluorine and nucleophilic, electrophilic, radical fluorinating reagents—are prepared from hydrogen fluoride (HF). This highly toxic corrosive gas is produced by the reaction of acid-grade fluorspar (>97% CaF 2 ) with sulfuric acid under harsh conditions. The use to produce fluorochemicals via a process that bypasses HF desirable but remains an unsolved problem because prohibitive insolubility . Inspired calcium phosphate biomineralization, we herein...
Abstract Calcium fluoride is the ultimate source of all fluorochemicals. Current synthetic approaches rely on use HF, generated from naturally occurring fluorspar and sulfuric acid. Methods for constructing E–F bonds directly CaF 2 have long been frustrated by its high lattice energy, low solubility impaired ion nucleophilicity. Little fundamental understanding reactivity Ca–F moieties available to guide methodology development; well-defined molecular species containing are extremely rare,...
Aiming at knowledge-driven design of novel metal-ceria catalysts for automotive exhaust abatement, current efforts mostly pertain to the synthesis and understanding well-defined systems. In contrast, technical are often heterogeneous in their metal speciation. Here, we unveiled rich structural dynamics a conventional impregnated Pd/CeO2 catalyst during CO oxidation. situ X-ray photoelectron spectroscopy operando absorption revealed presence metallic oxidic Pd states reaction. Using transient...
The direct catalytic conversion of atmospheric CO2 to valuable chemicals is a promising solution avert negative consequences rising concentration. However, heterogeneous catalysts efficient at low partial pressures still need be developed. Here, we explore Co/CeO2 as catalyst for the methanation diluted streams. This material displays an excellent performance reaction temperatures 175 °C and 0.4 mbar (the concentration). To gain mechanistic understanding this unusual activity, employed in...
The reactivity of an N-heterocyclic boryloxy (NHBO) ligated aluminyl compound has been harnessed for main-group-mediated dehydrogenative dual activation ammonia. Al(I) system K[{(HCDippN)2BO}2Al] reacts with excess NH3 to give the Al(III) bis(amide) K[{(HCDippN)2BO}2Al(NH2)2] and in process generates H2. initial stage reaction proceeds via formal N-H oxidative addition at (via a coordination/proton shuttling sequence) aluminium(III) primary amido hydride. Subsequent protonolysis strongly...
The reactivity of an N‐heterocyclic boryloxy (NHBO) ligated aluminyl compound has been harnessed for main‐group‐mediated dehydrogenative dual activation ammonia. Al(I) system K[{(HCDippN)2BO}2Al] reacts with excess NH3 to give the Al(III) bis(amide) K[{(HCDippN)2BO}2Al(NH2)2] and in process generates H2. initial stage reaction proceeds via formal N–H oxidative addition at (via a coordination/proton shuttling sequence) aluminium(III) primary amido hydride. Subsequent protonolysis strongly...
The homogeneous catalytic functionalization of methane is extremely challenging due to the relative nonpolarity and high C–H bond strength this hydrocarbon. Here, using quantities (10 mol %) CpMn(CO)3 or Cp*Re(CO)3, conversion benzene bonds C–Be H–Be by CpBeBeCp has been achieved under photochemical conditions. Possible intermediates in beryllation reactions─trans-bis(beryllyl)-manganese -rhenium complexes─were also isolated. Quantum chemical calculations indicate that inherent properties...
The first example of photocatalytic trifluoromethoxylation arenes and heteroarenes under continuous-flow conditions is described. Application microreactor technology allowed to reduce the residence time up 16 times in comparison batch procedure, while achieving similar or higher yields. In addition, use inorganic bases was demonstrated increase reaction yield conditions.
Abstract By exploiting the electronic capabilities of N‐heterocyclic boryloxy (NHBO) ligand, we have synthesized “naked” acyclic gallyl [Ga{OB(NDippCH) 2 } ] − and indyl [In{OB(NDippCH) anions (as their [K(2.2.2‐crypt)] + salts) through K abstraction from [KGa{OB(NDippCH) [KIn{OB(NDippCH) using 2.2.2‐crypt. These systems represent first O‐ligated gallyl/indyl systems, are ultimately accessed cyclopentadienyl Ga I /In precursors by substitution chemistry, display nucleophilic reactivity which...
Abstract By exploiting the electronic capabilities of N‐heterocyclic boryloxy (NHBO) ligand, we have synthesized “naked” acyclic gallyl [Ga{OB(NDippCH) 2 } ] − and indyl [In{OB(NDippCH) anions (as their [K(2.2.2‐crypt)] + salts) through K abstraction from [KGa{OB(NDippCH) [KIn{OB(NDippCH) using 2.2.2‐crypt. These systems represent first O‐ligated gallyl/indyl systems, are ultimately accessed cyclopentadienyl Ga I /In precursors by substitution chemistry, display nucleophilic reactivity which...
The ambiphilic reactivity of alkyl sulfonyl fluorides in the stereoselective synthesis diverse cyclopropanes from ole-fins under palladium(II) catalysis is presented. fluoride functionality serves as both an acidifying group and internal oxidant within ambiphile, enabling successive carbopalladation oxidative addition steps catalytic cycle, respectively. transformation grants access to cis-substituted exhibits broad compatibility with various fluorides, including those bearing –CN, –CO2R,...
The major source of fluoride, namely calcium difluoride (CaF2), is derived from the mineral fluorspar. Recent advances in activation CaF2 via mechanochemical methods have inspired investigation fundamental properties Ca–F bonds molecular complexes. However, paucity well-defined Ca–F-containing complexes undermines systematic understanding factors governing nucleophilic fluoride delivery. Here we report use a multidentate bis(phenoxide) ligand based on 1,4,7-triazacyclononane (TACN) scaffold...
Abstract The major source of fluoride, namely calcium difluoride (CaF 2 ), is derived from the mineral fluorspar. Recent advances in activation CaF via mechanochemical methods have inspired investigation fundamental properties Ca–F bonds molecular complexes. However, paucity well‐defined Ca–F‐containing complexes undermines systematic understanding factors governing nucleophilic fluoride delivery. Here we report use a multidentate bis(phenoxide) ligand based on 1,4,7‐triazacyclononane (TACN)...
Abstract The major source of fluoride, namely calcium difluoride (CaF 2 ), is derived from the mineral fluorspar. Recent advances in activation CaF via mechanochemical methods have inspired investigation fundamental properties Ca–F bonds molecular complexes. However, paucity well‐defined Ca–F‐containing complexes undermines systematic understanding factors governing nucleophilic fluoride delivery. Here we report use a multidentate bis(phenoxide) ligand based on 1,4,7‐triazacyclononane (TACN)...
Abstract The direct catalytic conversion of atmospheric CO 2 to valuable chemicals is a promising solution avert negative consequences rising concentration. However, heterogeneous catalysts efficient at low partial pressures still need be developed. Here, we explore Co/CeO as catalyst for the methanation diluted streams. This material displays an excellent performance reaction temperatures 175 °C and 0.4 mbar (the concentration). To gain mechanistic understanding this unusual activity,...
Abstract Aiming at knowledge‐driven design of novel metal–ceria catalysts for automotive exhaust abatement, current efforts mostly pertain to the synthesis and understanding well‐defined systems. In contrast, technical are often heterogeneous in their metal speciation. Here, we unveiled rich structural dynamics a conventional impregnated Pd/CeO 2 catalyst during CO oxidation. situ X‐ray photoelectron spectroscopy operando absorption revealed presence metallic oxidic Pd states reaction. Using...
Operando-Spektroskopie wurde genutzt, um das dynamische Verhalten von Pd-Einzelatomen, Pd-Clustern und Pd-Nanopartikeln auf Ceroxidträgern während der CO-Oxidation zu erfassen. In ihrem Forschungsartikel (e202200434) identifizieren Emiel J. M. Hensen et al. die katalytische Rolle verschiedener Pd-Spezies durch eine Kombination In-situ-Spektroskopie mit transienter stationärer kinetischer Analyse. Hochdisperse Pd-Oxo-Spezies Pd-Grenzflächen katalysieren bei niedrigen Temperaturen,...