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Concept

Imidazole

Publications associées (30)

New Polymers from Biomass-Derived Hydroxycinnamic Acid Derivatives

Ghezae Tekleab

Polymers play a central role in shaping our world across various fields, but their heavy reliance on petrochemicals poses climate change, environmental and health risks. To address and alleviate these issues, transitioning to sustainable polymers, sourced ...

EPFL2024

TiCl3-Mediated Reductive Cyclization of Tetrasubstituted Alkenes and Enol Esters Bearing a 2-Nitrophenyl Substituent

Dina Boyarskaya

Indole is one of the most important heterocycles widely present in bioactive natural products, pharmaceuticals, agrochemicals and materials. Being easily accessible, the 2-nitrostyrenes are attractive starting materials for the indole synthesis and the Cad ...

EPFL2023

Electrolyte engineering via ether solvent fluorination for developing stable non-aqueous lithium metal batteries

Mounir Driss Mensi

Fluorination of solvents, useful for non-aqueous lithium-based batteries, improves the electrochemical stability but decreases the ionic conductivity. Here, the authors report a targeted functionalization of an ether solvent to balance the electrolyte ioni ...

Nature Portfolio2023

Synthetic chemistry with nitrous oxide and triazenes

Iris Roswitha Landman

Nitrous oxide (N2O) has gained much interest because of its physiological effects ("laughing gas") and its negative environmental impact ("greenhouse gas", "ozone-depleting substance"): It has a lifetime of more than 100 years in the atmosphere. Its persis ...

EPFL2022

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

Alkynyl triazenes enable divergent syntheses of 2-pyrones

Kay Severin, Nicolai Cramer, Carl Thomas Bormann, Jin Fay Tan

The 2-pyrone motif occurs frequently in bioactive natural products and is appreciated as synthetic intermediates. However, only few methods allow for diversifying functional group modifications on this relevant heterocycle. The distinct properties of 1-alk ...

2021

Nanocapillary confinement of imidazolium based ionic liquids

Aleksandra Radenovic, Sanjin Marion, Sebastian James Davis

Room temperature ionic liquids are salts which are molten at or around room temperature without any added solvent or solution. In bulk they exhibit glass like dependence of conductivity with temperature as well as coupling of structural and transport prope ...

2020

Divergent Synthesis of Densely Substituted Arenes and Pyridines via Cyclotrimerization Reactions of Alkynyl Triazenes

Kay Severin, Nicolai Cramer, Carl Thomas Bormann, Jin Fay Tan, Florian Gérald Abela, Frederick Mark Chadwick

Densely substituted fused aromatic triazenes can be prepared by [2 + 2 + 2] cyclotrimerization reactions of 1-alkynyl triazenes. The Cp*Ru-catalyzed cyclization proceeds well with both simple alkynyl triazenes and tethered 1-diynyl triazenes. Attractively, ...

2019

Intricacies of Cation-Anion Combinations in Imidazolium Salt-Catalyzed Cycloaddition of CO2 Into Epoxides

Paul Joseph Dyson, Gabor Laurenczy, Felix Daniel Bobbink, Martin Hulla, Dmitry Vasilyev, Florent Menoud

The cycloaddition of CO2 into epoxides catalyzed by imidazolium and related salts continues to attract attention due to the industrial importance of the cyclic carbonate products. The mechanism of the imidazolium-catalyzed transformation has been proposed ...

2018

Dyes, Radicals and Nitrous Oxide Adducts Derived from N-Heterocyclic Carbenes

Léonard Yannick Maurice Eymann

N-Heterocyclic carbenes are able to form covalent adducts with nitrous oxide (N2O) under ambient conditions. This thesis summarizes the studies of these adducts and their reactivity. A ditopic carbanionic N-heterocyclic carbene was found to react with nit ...

EPFL2018

High Susceptibility of Histidine to Charge Solvation Revealed by Cold Ion Spectroscopy

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev

Histidine remained the last aromatic amino acid for which the intrinsic spectroscopic properties and structures were obscure. We measured the UV and IR spectra of protonated histidine, isolated in the gas phase, using photofragmentation cold ion spectrosco ...

Wiley-Blackwell2017

Base-Free Transfer Hydrogenation with an Ionic-Liquid-Supported Ruthenium eta(6)-Arene Bis(pyrazolyl)methane Catalyst

Paul Joseph Dyson, Andrew Douglas Phillips, Francisco Sepulveda

Ruthenium complexes of the type [RuCl(eta(6)-arene)-(NN)]X (X = BF4 or BPh4) featuring an eta(6)-arene ligand modified with an imidazolium ring and incorporating the bis(azo) chelating (NN) ligands 2-hydroxyphenylbis(3,5-dimethylpyrazol-1-yl) methane or 2- ...

Wiley-Blackwell2017

Synthesis of Cross-linked Ionic Poly(styrenes) and their Application as Catalysts for the Synthesis of Carbonates from CO2 and Epoxides

Paul Joseph Dyson, Zhaofu Fei, Felix Daniel Bobbink, Antoine Philippe Van Muyden, Aswin Gopakumar

A series of dicationic styrene-functionalized imidazolium-based salts, in which the two imidazolium rings are bridged by a functionalized spacer, are prepared. The salts are polymerized to afford cross-linked imidazolium-based ionic polystyrene materials, ...

Wiley-VCH Verlag2017

New Insights Into the Role of Imidazolium-Based Promoters for the Electroreduction of CO2 on a Silver Electrode

Michael Graetzel, Paul Joseph Dyson, Rosario Scopelliti, Marcel Roland Schreier, Dmitry Vasilyev, Pui Shan Genevieve Lau

The electrochemical reduction of CO2 to CO is a reaction of central importance for sustainable energy conversion and storage. Herein, structure activity relationships of a series of imidazolium-based cocatalysts for this reaction are described, which demon ...

Amer Chemical Soc2016

Lewis acid Catalyzed Annulations of Donor-Acceptor Aminocyclopropanes and Aminocyclobutanes

Sophie Lucie Racine

Organic molecules are indispensable have greatly contributed to the confort of our modern life. Nevertheless, humanity is facing now new challenges such as environmental issues and emerging drug resistances. In order to solve these major concerns, chemists ...

EPFL2016

Designing interactions across interfaces in ionic liquids

Valentin Michael Manzanares

Ionic liquids (ILs) have attracted much attention because of their unusual charac- teristics (vapor pressure, condictivity, etc.). Furthermore, they can be designed to display desired properties specific to an application (task-specific ionic liquid, TSILs ...

EPFL2016

Tuning the Reactivity of Isocyano Group: Synthesis of Imidazoles and Imidazoliums from Propargylamines and Isonitriles in the Presence of Multiple Catalysts

Jieping Zhu, Qian Wang, Shuo Tong

The reaction of propargyl amines with tert-butylisonitrile in the presence of a catalytic amount of both Yb(OTf)3 and AgOTf afforded imidazoles, whereas the same reaction with primary and secondary alkylisonitriles, as well as arylisonitriles, in the prese ...

Wiley-Blackwell2015

Influence of Elemental Iodine on Imidazolium-Based Ionic Liquids: Solution and Solid-State Effects

Paul Joseph Dyson, Rosario Scopelliti, Zhaofu Fei, Felix Daniel Bobbink, Emilia Paunescu

Ionic liquids doped with I-2, usually resulting in the formation of polyiodide anions, are extensively used as electrolytes and in iodination reactions. Herein, NMR spectroscopy and single-crystal X-ray diffraction were used to rationalize the structures o ...

2015

Exploring the aqueous vertical ionization of organic molecules by molecular simulation and liquid microjet photoelectron spectroscopy

Jeremy Samuel Arey, Peter Rudolf Tentscher, Jennifer Guerard

To study the influence of aqueous solvent on the electronic energy levels of dissolved organic molecules, we conducted liquid microjet photoelectron spectroscopy (PES) measurements of the aqueous vertical ionization energies (VIEaq) of aniline (7.49 eV), v ...

Amer Chemical Soc2015

Improved biocompatibility of polyethylenimine (PEI) as a gene carrier by conjugating urocanic acid: In vitro and in vivo

Jeffrey Alan Hubbell, Irina Krier

Polyethylenimine (PEI) is a promising gene carrier among polymeric vectors because of its high transfection efficiency, buffering capacity, which is responsible for its escape from endosomes, facility of modification, reasonable price and wide range of mol ...

Polymer Soc Korea2015