A5087272505- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Organometallic Complex Synthesis and Catalysis
- Asymmetric Hydrogenation and Catalysis
- Metal-Catalyzed Oxygenation Mechanisms
- Catalytic C–H Functionalization Methods
- Metal complexes synthesis and properties
- Crystallography and molecular interactions
- Magnetism in coordination complexes
- Carbon dioxide utilization in catalysis
- Organoboron and organosilicon chemistry
- Catalytic Cross-Coupling Reactions
- CO2 Reduction Techniques and Catalysts
- Synthesis and Catalytic Reactions
- Metalloenzymes and iron-sulfur proteins
- Catalytic Alkyne Reactions
- Boron Compounds in Chemistry
- Ammonia Synthesis and Nitrogen Reduction
- Synthetic Organic Chemistry Methods
- Lanthanide and Transition Metal Complexes
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Synthesis and characterization of novel inorganic/organometallic compounds
- Electrocatalysts for Energy Conversion
- Muscle Physiology and Disorders
- Chemical synthesis and alkaloids
Utrecht University
2018-2025
Yale University
2017-2020
University of Zurich
2017
University of Amsterdam
1990-2017
Institute for Atomic and Molecular Physics
2016
Westfriesgasthuis
2016
Vrije Universiteit Amsterdam
2000-2015
Institute for Molecular Science
2015
Amsterdam University of Applied Sciences
2015
Institute of Catalysis and Petrochemistry
2015
Coordination of FeCl3 to the redox-active pyridine–aminophenol ligand NNOH2 in presence base and under aerobic conditions generates FeCl2(NNOISQ) (1), featuring high-spin FeIII an NNOISQ radical ligand. The complex has overall S = 2 spin state, as deduced from experimental computational data. ligand-centered couples antiferromagnetically with Fe center. Readily available, well-defined, air-stable 1 catalyzes challenging intramolecular direct C(sp3)–H amination unactivated organic azides...
Transition-metal-based molecular complexes are a class of catalyst materials for electrochemical CO2 reduction to CO that can be rationally designed deliver high catalytic performance. One common mechanistic feature these electrocatalysts developed thus far is an electrogenerated reduced metal center associated with reduction. Here we report heterogenized zinc-porphyrin complex (zinc(II) 5,10,15,20-tetramesitylporphyrin) as electrocatalyst delivers turnover frequency 14.4 site-1 s-1 and...
Transition-metal-catalyzed [2+2+2] cyclo(co)trimerization reactions are a powerful methodology to synthesize various complex multi-substituted (poly)cyclic molecules in single step with optimal atom efficiency. Ever since the discovery, reaction has been plagued by issues concerning regio- and chemoselectivity. Over last decades many advances have made overcome these by, for example, employing regio-directing groups or tethering partners together an intramolecular approach. These solutions,...
Coordination of the redox-active tridentate NNO ligand L(H2) to Pd(II) yields paramagnetic iminobenzosemiquinonato complex 3. Single-electron reduction 3 diamagnetic amidophenolato 4, capable activating aliphatic azide 5. Experimental and computational studies suggest a redox-noninnocent pathway wherein facilitates intramolecular ligand-to-substrate single-electron transfer generate an open-shell singlet "nitrene-substrate radical, radical", enabling subsequent radical-type C-H amination...
Cobalt-porphyrin-catalysed intramolecular ring-closing C-H bond amination enables direct synthesis of various N-heterocycles from aliphatic azides. Pyrrolidines, oxazolidines, imidazolidines, isoindolines and tetrahydroisoquinoline can be obtained in good to excellent yields a single reaction step with an air- moisture-stable catalyst. Kinetic studies the combination DFT calculations reveal metallo-radical-type mechanism involving rate-limiting azide activation form key cobalt(III)-nitrene...
Abstract Coordination of the novel redox‐active phosphine‐appended aminophenol pincer ligand (PNO H2 ) to Pd II generates a paramagnetic complex with persistent ligand‐centered radical. The undergoes fully reversible single‐electron oxidation and reduction. Homolytic bond activation diphenyldisulfide by reduced species leads ligand‐based mixed‐valent dinuclear palladium single bridging thiolate ligand. Mechanistic investigations support an unprecedented intramolecular ligand‐to‐disulfide...
The synthesis, spectroelectrochemical characterization (ultraviolet-visible and nuclear magnetic resonance), solid state structures, computational metric parameters of three isostructural PdCl(NNO) complexes 1 [PdCl(NNO(ISQ))], 2 {[PdCl(NNO(AP))](-)}, 5 {[PdCl(NNO(IBQ))](+)} (NNO = o-aminophenol-derived redox-active ligand with a pendant pyridine) different NNO oxidation states are described. reduced diamagnetic complex readily reacts halogenated solvents, including lattice solvent from...
We evaluated the implementation and effectiveness of adjunctive dexamethasone in adults with meningococcal meningitis.We compared 2 Dutch prospective nationwide cohort studies on community-acquired meningitis. A total 258 patients CSF culture-proven meningitis were enrolled between 1998 2002, before routine therapy was introduced, 100 from March 2006 to January 2011, after guidelines recommended dexamethasone.Dexamethasone administered 43 (17%) 1998-2002 86 96 (90%) 2006-2011 (p < 0.001),...
Abstract A naphthyridine‐derived expanded pincer ligand is described that can host two copper(I) centers. The proton‐responsive undergo reversible partial and full dearomatization of the naphthyridine core, which enables cooperative activation H 2 giving an unusual butterfly‐shaped Cu 4 complex.
Abstract The synthesis, reactivity, and potential of well‐defined dinuclear gold complexes as precursors for dual catalysis are explored. Using the preorganizing abilities ditopic PN H P iPr ( L ) ligand, Au I –Au complex 1 mixed‐valent III 2 provide access to structurally characterized chlorido‐bridged cationic species 3 4 upon halide abstraction. For , this transformation involves unprecedented two‐electron oxidation redox‐active generating a highly rigidified environment core. Facile...
The PNNP expanded pincer ligand can bind two iron centers in close proximity and display heterolytic homolytic metal–ligand cooperativity.
Understanding how multicopper oxidases (MCOs) reduce oxygen in the trinuclear copper cluster (TNC) is of great importance for development catalysts reduction reaction (ORR). Herein, we report a mechanistic investigation into ORR activity dinuclear complex [Cu2L(μ-OH)]3+ (L = 2,7-bis[bis(2-pyridylmethyl)aminomethyl]-1,8-naphthyridine). This inspired by T3 site found MCO active and confines Cu centers rigid scaffold. We show that electrochemical follows proton-coupled electron transfer pathway...
Developing multimetallic complexes with tunable metal-metal interactions has long been a target of synthetic inorganic chemistry efforts due to the unique properties that such compounds can exhibit. However, understanding relationships between bonding and chemical is challenging system-dependent factors influence metal-ligand interactions, including ligand identity, coordination geometry, distance. In this work, we apply X-ray absorption emission spectroscopy quantum calculations describe...
Abstract The tuning of metal–metal interactions in multinuclear assemblies is a challenge. Selective P coordination redox‐active PNO ligand to Au I followed by homoleptic metalation the NO pocket with Ni II affords unique trinuclear Au–Ni–Au complex. This species features two antiferromagnetically coupled ligand‐centered radicals and double intramolecular d 8 –d 10 interaction, as supported spectroscopic, single‐crystal X‐ray diffraction, computational data. A corresponding cationic...
Developing multimetallic complexes with tunable metal-metal interactions has long been a target of synthetic inorganic chemistry efforts, due to the unique and desirable properties that such compounds can exhibit. However, understanding relationship between bonding chemical in is challenging system-dependent factors influence metal-ligand including ligand identity, coordination geometry, distance. In this work we apply combination X-ray absorption emission spectroscopy quantum calculations...
The direct functionalization of unactivated hydrocarbons remains a significant challenge in modern chemistry. In this study, we demonstrate that simple ruthenium complex featuring chelating tBuPN ligand can mediate the nucleophilic aromatic substitution hydrogen (SNArH) benzene. Key intermediates were kinetically trapped low-temperature NMR experiments, providing crucial insights into reaction mechanism. These findings are further supported by isotopic labeling and comprehensive DFT studies....
We report the synthesis and characterisation of naphthyridine-based dippDAMN dippNDC ligands, bearing pendant secondary amine amide donors, respectively. additionally their deprotonation chemistry reactivity with dialkylmagnesium Grignard reagents. The reactions yield structurally distinct LMg2Cl2·(THF)n complexes, dippNDC-based complex exhibiting reduced steric strain from ligand around Mg2Cl2 core. Comparison profiles complexes reveals that this stems difference in binding modes which case...
We report the synthesis, isolation, and characterisation of an N-heterocyclic germylene (NHGe) derived from a two-electron reduced Mg-synthon redox-active dippNBA ligand. This NHGe features vacant binding pocket capable coordinating various metals, which enables formation heterobimetallic Ge–Zn Ge–Mg complexes. Electronic structure calculations reveal that interactions are weak, whilst between metals found for heterodinuclear complex stronger. These findings highlight how nature Ge–M adapts...
The absence of residual solvent in metal precursors can be key importance for the successful preparation complexes or materials. Herein, we describe methods quantitation coordinated tetrahydrofuran (THF) that binds to Fe[N(SiMe3)2]2, a commonly used iron synthon, when prepared according common literature procedures. A simple method amount THF using 1H NMR spectroscopy is highlighted. Finally, detailed synthetic procedure described synthesis THF-free Fe[N(SiMe3)2]2.
Abstract The facile and tunable preparation of unique dinuclear [(L ⋅ )PdXPd(L )] complexes (X=Cl or N 3 ), bearing a ligand radical on each Pd, is disclosed, as well their magnetochemistry in solution solid state reported. Chloride abstraction from [PdCl( NNO ISQ ( =iminosemiquinonato) with TlPF 6 results an unusual monochlorido‐bridged open‐shell diradical species, [{Pd( )} 2 (μ‐Cl)] + , unusually small Pd‐Cl‐Pd angle (ca. 93°, determined by X‐ray). This suggests intramolecular d 8 –d...
Coordination of redox-active ligands to metals is a compelling strategy for making reduced complexes more accessible. In this work, we explore the use formazanate in low-coordinate iron chemistry. Reduction an iron(II) precursor occurs at milder potentials than analogous non-redox-active β-diketiminate complexes, and three-coordinate formazanate-iron compound characterized detail. Structural, spectroscopic, computational analysis show that ligand undergoes reversible ligand-centered...
Low-nuclearity copper hydrides are rare and few well-defined dicopper have been reported. Herein, we describe the first example of a structurally characterized anionic hydride complex. This complex does not display typical reactivity associated with low-nuclearity hydrides, such as alcoholysis or insertion reactions. Instead, its stoichiometric catalytic is akin to that clusters. The distinct ascribed robust dinuclear core bound tightly within dinucleating ligand scaffold.