A5019575526- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Metal complexes synthesis and properties
- Catalytic Cross-Coupling Reactions
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Magnetism in coordination complexes
- Radical Photochemical Reactions
- Lanthanide and Transition Metal Complexes
- CO2 Reduction Techniques and Catalysts
- Catalytic C–H Functionalization Methods
- Organic Light-Emitting Diodes Research
- Polyoxometalates: Synthesis and Applications
- Supramolecular Chemistry and Complexes
- Luminescence and Fluorescent Materials
- Metal-Organic Frameworks: Synthesis and Applications
- Organoboron and organosilicon chemistry
- Advanced biosensing and bioanalysis techniques
- Coordination Chemistry and Organometallics
- Metal-Catalyzed Oxygenation Mechanisms
- Nanocluster Synthesis and Applications
- Oxidative Organic Chemistry Reactions
- Gender and Women's Rights
- Photochromic and Fluorescence Chemistry
- Molecular Junctions and Nanostructures
- Perovskite Materials and Applications
University of Basel
2021-2025
Indian Institute of Technology Mandi
2024-2025
University of Münster
2014-2023
University of Ottawa
2019
York University
2019
Indian Institute of Technology Guwahati
2012
ConspectusOver the past two decades, self-assembly of supramolecular architectures has become a field intensive research due to wide range applications for resulting assemblies in various fields such as molecular encapsulation, catalysis, drug delivery, metallopharmaceuticals, chemical and photochemical sensing, light-emitting materials. For these purposes, large number coordination-driven metallacycles metallacages featuring different sizes shapes have been prepared investigated. Almost all...
Coordination complexes of precious metals with the d6 valence electron configuration such as Ru(II), Os(II) and Ir(III) are used for lighting applications, solar energy conversion photocatalysis. Until now, made from abundant first-row transition competitive photophysical photochemical properties have been elusive. While previous research efforts focused mostly on Fe(II), we disclose that isoelectronic Cr(0) gives access to higher photoluminescence quantum yields excited-state lifetimes when...
Iridium is used in commercial light-emitting devices and photocatalysis but among the rarest stable chemical elements. Therefore, replacing iridium(III) photoactive molecular complexes with abundant metals of great interest. First-row transition generally tend to yield poorer luminescence behavior, it remains difficult obtain excited states redox properties that exceed those noble-metal-based photocatalysts. Here, we overcome these challenges a nonprecious second-row metal. Tailored...
Abstract Two tetraphenylethylene (TPE) bridged tetraimidazolium salts, [H 4 L ‐Et](PF 6 ) and ‐Bu](PF , were used as precursors for the synthesis of dinuclear Ag I Au tetracarbene complexes [Ag 2 ( ‐Et)](PF ‐Bu)](PF [Au . The salts show almost no fluorescence Φ F <1 %) in dilute solution while their NHC display “turn‐on” up to 47 %). This can be ascribed rigidification mediated by restriction intramolecular rotation within TPE moiety upon complexation. DFT calculations confirm that metals...
Abstract A procedure for the synthesis of three‐dimensional hexakisimidazolium cage compounds has been developed. The reaction trigonal trisimidazolium salts H 3 L(PF 6 ) , decorated with three N‐olefinic pendants, and silver oxide yielded trinuclear trisilver(I) hexacarbene molecular cylinders type [Ag L 2 ] 3+ olefinic pendants from two different tricarbene ligands arranged in pairs. Subsequent UV irradiation gave cyclobutane links between tris‐NHC [2+2] cycloaddition reactions, thereby...
The combination of π-donating amido with π-accepting pyridine coordination units in a tridentate chelate ligand causes strong nephelauxetic effect homoleptic Cr
Many organometallic iridium(III) complexes have photoactive excited states with mixed metal-to-ligand and intraligand charge transfer (MLCT/ILCT) character, which form the basis for numerous applications in photophysics photochemistry. Cobalt(III) analogous MLCT excited-state properties seem to be unknown yet, despite fact that cobalt(III) can adopt identical low-spin d6 valence electron configurations due their close chemical relationship. Using a rigid tridentate chelate ligand (LCNC),...
Square-planar NiII complexes and their electronically excited states play key roles in cross-coupling catalysis could offer new opportunities to complement well-known isoelectronic PtII luminophores. Metal-to-ligand charge transfer (MLCT) deactivation pathways are particularly relevant these contexts. We sought extend the lifetimes of 3MLCT square-planar by creating coordination environments that seemed well adapted 3d8 valence electron configuration. Using a rigid tridentate chelate ligand,...
Light-triggered dissociation of ligands forms the basis for many compounds interest photoactivated chemotherapy (PACT), in which medicinally active substances are released or "uncaged" from metal complexes upon illumination. Photoinduced ligand is usually irreversible, and recent studies performed context PACT focused on ruthenium(II) polypyridines related heavy complexes. Herein, we report a first-row transition complex, photoinduced spontaneous recoordination unit occurs. Two...
Substituting precious elements in luminophores and photocatalysts by abundant first-row transition metals remains a significant challenge, iron continues to be particularly attractive owing its high natural abundance low cost. Most complexes known date face severe limitations due undesirably efficient deactivation of luminescent photoredox-active excited states. Two new iron(III) with structurally simple chelate ligands enable straightforward tuning ground state properties, contrasting...
Abstract Highly selective, narcissistic self‐sorting has been observed in the one‐pot synthesis of three organometallic molecular cylinders type [M 3 {L‐(NHC) } 2 ](PF 6 ) (M=Ag + , Au ; L=1,3,5‐benzene, triphenylamine, or 1,3,5‐triphenylbenzene) from L‐(NHC) and silver(I) gold(I) ions. The contain only one tris‐NHC ligand with no crossover products detectable. Transmetalation ligands Ag to a reaction retention supramolecular structures is also demonstrated. High‐fidelity was benzene‐bridged...
Sensitized triplet–triplet annihilation upconversion is a promising strategy to use visible light for chemical reactions requiring the energy input of UV photons. This avoids unsafe ultraviolet sources and can mitigate photo-damage provide access reactions, which filter effects hamper direct excitation. Here, we report new approach make blue-to-UV more amenable photochemical applications. The tethering naphthalene unit cyclometalated iridium(III) complex yields bichromophore with high...
The metal-controlled self-assembly of nanometer-sized trinuclear cylinder-like assemblies is described. 1,3,5-triphenylbenzene-derived trisimidazolium salt [1](PF6)3 reacts with 1.5 equiv Ag2O to yield the AgI hexacarbene complex [2](PF6)3, where three ions are sandwiched in between two C3-symmetric tris-NHC ligands. Transmetalation [2](PF6)3 3 [AuCl(SMe2)] or CuI yields AuI [3](PF6)3 [4](PF6)3, respectively, retention metallosupramolecular structure. 1,3,5-triphenylbenzene ligand gold...
We report the electrochemiluminescence (ECL) of a 3d
Photocatalysis emerges as an efficient and versatile tool for the preparation of organic compounds via development new methodologies photosensitizers. Mostly UV blue light irradiation are used such reactions. Red is low energy light, it less harmful has more penetration depth. Hence red driven photocatalysis would be suitable preparing value added products. absorbing photosensitizers mostly based on rare expensive metals. In this review, we describe recent developments Earth‐abundant...
Abstract Eine Strategie für die Synthese dreidimensionaler Hexakisimidazolium‐Käfigverbindungen wurde entwickelt. Die Reaktion von trigonalen Trisimidazolium‐Salzen H 3 L(PF 6 ) mit drei terminalen N‐Olefin‐Substituenten und Silberoxid ergibt molekulare Trisilber‐Hexacarben‐Zylinder des Typs [Ag (L) 2 ] 3+ , in denen zwei unterschiedlichen Tricarben‐Liganden paarweise angeordnet sind. UV‐Bestrahlung führt über [2+2]‐Cycloadditionen zu Cyclobutan‐Brücken zwischen den beiden Tris‐NHC‐Liganden...
Abstract The single‐step multicomponent self‐assembly of molecular squares featuring four bridging benzobiscarbenes and Pd II (allyl) or Ir I (COD) vertices is presented. Four equivalents the linear benzobisimidazolium salt [ 1 ](PF 6 ) 2 react with two [Pd(allyl)Cl] [IrCl(COD)] in presence Cs CO 3 to yield tetranuclear octacarbene 4 (M=Pd) (M=Ir), respectively. Compounds feature exclusively M–carbon bonds making them first purely organometallic squares.
Abstract Mit den Tetraphenylethylen(TPE)‐verbrückten Tetraimidazolium‐Salzen [H 4 L ‐Et](PF 6 ) und ‐Bu](PF wurden die zweikernigen Ag I ‐ Au ‐Tetracarben‐Komplexe [Ag 2 ( ‐Et)](PF , ‐Bu)](PF [Au synthetisiert. In verdünnter Lösung zeigen Tetraimidazolium‐Salze fast keine Fluoreszenz (Φ F <1 %), während NHC‐Komplexe stark fluoreszieren bis zu 47 %). Die Komplexbildung führt zur Versteifung der TPE‐Einheit Verhinderung intramolekulare Rotation innerhalb TPE‐Einheit. DFT‐Rechnungen...
The coupling of organolithium reagents, including strongly hindered examples, at cryogenic temperatures (as low as -78 °C) has been achieved with high-reactivity Pd-NHC catalysts. A temperature-dependent chemoselectivity trigger developed for the selective aryl bromides in presence chlorides. Building on this, a one-pot, sequential strategy is presented rapid construction advanced building blocks. Importantly, one-shot addition alkyllithium compounds to Pd cross-coupling reactions achieved,...
Abstract Narzisstische Selbstsortierung wurde bei der Eintopfsynthese von drei metallorganischen molekularen Zylindern des Typs [M 3 {L‐(NHC) } 2 ](PF 6 ) (M=Ag + , Au ; L=Benzol, Triphenylamin oder 1,3,5‐Triphenylbenzol) ausgehend L‐(NHC) und Silber(I)‐ Gold(I)‐Ionen beobachtet. Die Zylinder enthalten stets nur einen Typ Tris‐NHC‐Liganden, ohne dass Heteroligand‐Verbindungen zu detektieren sind. Transmetallierung Tris‐NHC‐Liganden Ag auf in einer Eintopfreaktion verläuft unter Erhaltung...
A new C3 -symmetric tris-imidazolium tribromide salt 3, featuring 1,3,5-substituted triethynylbenzene, was used for the preparation of a trinuclear PdII pyridine-enhanced precatalyst stabilization and initiation-type (PEPPSI) complex by triple C2 deprotonation followed addition PdCl2 . Trinuclear possessing combination NHC PPh3 ligands has also been synthesized. The corresponding mononuclear palladium(II) complexes have synthesized comparison purpose. All these characterized using NMR...
Diacylglycerol (DAG) regulates a broad range of cellular functions including tumor promotion, apoptosis, differentiation, and growth. Thus, the DAG-responsive C1 domain protein kinase C (PKC) isoenzymes is considered to be an attractive drug target for treatment cancer other diseases. To develop effective PKC regulators, we conveniently synthesized (hydroxymethyl)phenyl ester analogues targeted DAG binding site within domain. Biophysical studies molecular docking analysis showed that...
We report a general and rapid chemoselective Kumada-Tamao-Corriu (KTC) cross-coupling of aryl bromides in the presence chlorides or triflates with functionalized Grignard reagents at 0 °C 15 min by using Pd-PEPPSI-IPentCl (C4). Nucleophiles electrophiles (or both) can contain Grignard-sensitive functional groups (-CN, -COOR, etc.). Control experiments together DFT calculations suggest that transmetallation is rate limiting for selective Br Cl/OTf reagents. One-pot sequential KTC/KTC...