Publications related to Carbene

Investigations about the Chemistry of Tetraarylethene- and Iridium-Based Luminophores

The work described in this thesis focuses on two classes of luminophores: tetraarylethene-based polymers and Ir(III) complexes with orthometalated ligands. Tetraarylethene-based polymers show aggregation-induced emission (AIE) and they are of interest for ...

EPFL2024

Photocatalyzed [2σ + 2σ] and [2σ + 2π] Cycloadditions for the Synthesis of Bicyclo[3.1.1]heptanes and 5- or 6-Membered Carbocycles

Jérôme Waser, Matthew Wodrich, André Bossonnet

We report the use of photocatalysis for the homolytic ring-opening of carbonyl cyclopropanes. In contrast to previous studies, our approach does not require a metal cocatalyst or a strong reductant. The carbonyl cyclopropanes can be employed for both [2σ + ...

2023

The acid-mediated isomerization of iridium(iii) complexes with cyclometalated NHC ligands: kinetic vs. thermodynamic control

Kay Severin, Farzaneh Fadaei Tirani, Anastasia Gitlina

The isomerization of iridium(III) complexes with metalated N-heterocyclic carbene (NHC) ligands was studied. The fac isomers of complexes with 1-phenyl-3-methylbenzimidazolin-2-ylidene or 1-phenyl-3-benzylbenzimidazolin-2-ylidene ligands are transformed cl ...

2023

Symmetry-Induced Singlet-Triplet Inversions in Non-Alternant Hydrocarbons

Anne-Clémence Corminboeuf, Jacob Terence Blaskovits, Marc Hamilton Folkmann Garner

Molecules with inversion of the singlet and triplet excited-state energies are highly promising for the development of organic light-emitting diodes (OLEDs). To date, azaphenalenes are the only class of molecules where these inversions have been identified ...

Wiley-VCH Verlag GmbH2023

Mapping Catalyst‐Solvent Interplay in Competing Carboamination/Cyclopropanation Reactions

Nicolai Cramer, Matthew Wodrich, Anne-Clémence Corminboeuf, Miyeon Chang, Simone Gallarati

Group 9 metals, in particular Rh III complexes with cyclopentadienyl ligands, are competent C–H activation catalysts. Recently, a Cp*Rh III catalyzed reaction of alkenes with N -enoxyphthalimides showed divergent outcome based on the solvent, with carboami ...

2022

Multiple Surface Site Three-Dimensional Structure Determination of a Supported Molecular Catalyst

Pierrick Berruyer, Moreno Lelli, David Benjamin Roger Antoine Gajan, Zhuoran Wang

The structural characterization of supported molecular catalysts is challenging due to the low density of active sites and the presence of several organic/organometallic surface groups resulting from the often complex surface chemistry associated with supp ...

AMER CHEMICAL SOC2022

Isolation, Characterisation and Reactivity of N-Heterocyclic Diazoolefins

Paul Varava

Examples for applications of nitrous oxide in organic synthesis remain rare up until today. First mayor contributions of our group were published in 2012, when nitrous oxide was successfully captured by N-heterocyclic carbenes. Subsequent studies investiga ...

EPFL2022

Asymmetric Cyclopropanation and Epoxidation via a Catalytically Formed Chiral Auxiliary

Jérôme Waser, Mikus Purins

For the enantioselective diversification of a single starting material, a different chiral catalyst is usually required for each transformation. Herein, we extend the concept of catalytically formed chiral auxiliary from hydrogenation to the asymmetric cyc ...

Wiley-VCH Verlag GmbH2022

Optimizing the Thermodynamics and Kinetics of the Triplet-Pair Dissociation in Donor–Acceptor Copolymers for Intramolecular Singlet Fission

Anne-Clémence Corminboeuf, Maria Fumanal Quintana

Singlet fission (SF) is a two-step process in which a singlet splits into two triplets throughout the so-called correlated triplet-pair (1TT) state. Intramolecular SF (iSF) materials, in particular, have attracted growing interest as they can be easily imp ...

2022

Tuning the π‐Accepting Properties of Mesoionic Carbenes: A Combined Computational and Experimental Study

Rosario Scopelliti, Kay Severin, Farzaneh Fadaei Tirani, Andrzej Sienkiewicz, Anne-Clémence Corminboeuf, Zhaowen Dong, Jacob Terence Blaskovits

Mesoionic imidazolylidenes are recognized as excellent electron-donating ligands in organometallic and main group chemistry. However, these carbene ligands typically show poor π-accepting properties. We have performed a computational analysis of 71 mesoion ...

2021

Three-membered cyclic digermylenes stabilised by an N-heterocyclic carbene dagger

Zhaowen Dong

Treatment of potassium salts of silole dianions with donor stabilised germanium dichlorides gave the anticipated silagermafulvenylidenes R2Si = Ge(Do) (R2Si = 1-silacyclopentadiendiyl, Do = N-heterocyclic carbene (NHC)) only as transient intermediates in a ...

2021

New Vinylation and Alkynylation Strategies with Hypervalent Iodine Reagents and Diazo Compounds

Guillaume Dominique Pisella

The development of a sequential copper-catalyzed oxy-alkynylation/intramolecular [4+2] cycloaddition of allenes and arenes was investigated at first. This one-pot protocol allowed the construction of complex polycylic architectures with high efficiency fro ...

EPFL2021

Nitrous oxide as a diazo transfer reagent: the synthesis of triazolopyridines

Kay Severin, Farzaneh Fadaei Tirani, Iris Roswitha Landman

Nitrous oxide is a potential diazo transfer reagent, but its applications in organic chemistry are scarce. Here, we show that triazolopyridines and triazoloquinolines are formed in the reactions of metallated 2-alkylpyridines or 2-alkylquinolines with N2O. ...

Royal Society of Chemistry2021

Structure and Reactivity of N-Heterocyclic Alkynyl Hypervalent Iodine Reagents

Rosario Scopelliti, Jérôme Waser, Farzaneh Fadaei Tirani, Matthew Wodrich, Eliott Hugo Joran Le Du

Ethynylbenziodoxol(on)e (EBX) cyclic hypervalent iodine reagents have become popular reagents for the alkynylation of radicals and nucleophiles, but only offer limited possibilities for further structure and reactivity fine-tuning. Herein, the synthesis of ...

2021

New Strategies for the Functionalization of Alkenes Exploiting Tethering Chemistry and Ring Strain

Bastian Antoine Rodolphe Claude Muriel

Amino alcohols, cyclopropanes and nitriles are privileged structural motifs found in the scaffold of natural products and bioactive compounds. In addition, they are versatile building blocks in organic chemistry. The development of new and increasingly eff ...

EPFL2021

Atomic Level Insights of Non-Noble Metal Catalysts for the Oxygen Evolution Reaction

Lichen Bai

The conversion of intermittent renewable energy resources in the form of chemical bond, such as hydrogen production from electrochemical water splitting, is a promising way to satisfy the future global energy demand and address the environmental issues. Th ...

EPFL2021

Colloidal Synthesis of Cu-M-S (M = V, Cr, Mn) Nanocrystals by Tuning the Copper Precursor Reactivity

Raffaella Buonsanti, Seyedehbehnaz Varandili, Valeria Mantella, James Richard Pankhurst

New ternary and higher order inorganic materials are needed for a large variety of applications, yet their synthesis still represents a chemistry challenge. Herein, we focus on the synthesis of Cu-M-S nanocrystals (where M = V, Cr, Mn) via a wet-chemistry ...

2020

Influence of N-heterocyclic carbenes (NHCs) on the hydrolysis of a diphosphene

Shubhajit Das

We report the influence of N-heterocyclic carbenes (NHCs) on the hydrolysis of a diphosphene TerP?PTer (1; Ter = 2,6-Mes(2)C(6)H(3); Mes = 2,4,6-Me3C6H2), a phosphorus-analogue of an alkene. The diphosphene 1 itself is completely inert towards water. Howev ...

ROYAL SOC CHEMISTRY2020

Modular Chiral N-Heterocyclic Carbene Ligands for the Nickel-Catalyzed Enantioselective C-H Functionalization of Heterocycles

Nicolai Cramer, Johannes Diesel

N-Heterocyclic carbenes (NHCs) are the ligands of choice in a large variety of transformations entailing different transition metals. However, the number and variety of chiral NHCs suitable as stereo-controlling ligands in asymmetric catalysis remains limi ...

2020

Data-Driven Advancement of Homogeneous Nickel Catalyst Activity for Aryl Ether Cleavage

Matthew Wodrich, Anne-Clémence Corminboeuf, Benjamin André René Meyer, Manuel Cordova, Boodsarin Sawatlon

The increasing urgency to make chemical processes more environmentally friendly while continuing to derive the chemicals required for modern society from renewable resources requires the development of a forthcoming generation of synthetic processes and th ...

AMER CHEMICAL SOC2020