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Concept

Quaternary ammonium cation

Publications associées (28)

High-Density Immobilization of TCEP on Silica Beads for Efficient Disulfide Reduction and Thiol Alkylation in Peptides

Christian Heinis

Tris-(2-carboxyethyl)phosphine (TCEP) linked to agarose beads is widely used for reducing disulfide bridges in proteins and peptides. The immobilization of TCEP on beads allows efficient removal after reduction to prevent its reaction with alkylating reage ...

2023

Structure-property relationships and mixed conductivity in layered hybrid perovskites based on phenyl-derived spacers

Algirdas Ducinskas

Hybrid halide perovskites are currently one of the most studied semiconductors. However, due to poor intrinsic and extrinsic stability, further developments to commercialize devices based on hybrid halide perovskites are limited. Many different strategies ...

EPFL2022

Effect of cetyltrimethylammonium chloride on various Escherichia coli strains and their inactivation kinetics by ozone and monochloramine

Urs von Gunten, Florian Frédéric Vincent Breider, Margaux Océane Voumard

Cethyltrimethylammonium chloride (CTMA) is one of the most used quaternary ammonium compounds (QACs) in consumer products. CTMA and other QACs are only partially eliminated in municipal wastewater treatment and they can interact with bacteria in biological ...

2022

Chiral Alkyl Amine Synthesis via Catalytic Enantioselective Hydroalkylation of Enecarbamates

Xile Hu, Srikrishna Bera, Deyun Qian

Chiral alkyl amines are omnipresent as bioactive molecules and synthetic intermediates. The catalytic and enantioselective synthesis of alkyl amines from readily accessible precursors is challenging. Here we develop a nickel-catalyzed hydroalkylation metho ...

AMER CHEMICAL SOC2021

The Solvent Effect on H2O2 Generation at Room Temperature Ionic Liquid|Water Interface

Hubert Girault

H2O2 is a versatile chemical and can be generated by the oxygen reduction reaction (ORR) in proton donor solution in molecular solvents or room temperature ionic liquids (IL). We investigated this reaction at interfaces formed by eleven hydrophobic ILs and ...

2021

A Two Step Postsynthetic Modification Strategy: Appending Short Chain Polyamines to Zn-NH2-BDC MOF for Enhanced CO2 Adsorption

Wendy Lee Queen, Mehrdad Asgari, Olga Trukhina, Ilia Kochetygov, Jordi Espin Marti, Anita Justin

Functionalizing metal–organic frameworks (MOFs) with amines is a commonly used strategy to enhance their performance in CO2 capture applications. As such, in this work, a two-step strategy to covalently functionalize NH2-containing MOFs with short chain po ...

2021

Presence of sub-inhibitory concentrations of quaternary ammonium compounds in water: effects on bacteria and their inactivation by ozone and monochloramine

Margaux Océane Voumard

Disinfection agents have been present in our daily lives for several decades in detergents or in personal care products, where their role is to prevent the spread of pathogenic microor-ganisms. One of the largest class of disinfection agents is quaternary ...

EPFL2021

Adaptation of Pseudomonas aeruginosa to constant sub-inhibitory concentrations of quaternary ammonium compounds

Giovanni Dietler, Urs von Gunten, Sandor Kasas, Florian Frédéric Vincent Breider, Leonardo Venturelli, Margaux Océane Voumard

Quaternary ammonium compounds (QACs) are widely used in consumer products for disinfection purposes. QACs are frequently detected in aquatic systems at sub-inhibitory concentrations and were found to affect the development of antimicrobial resistance if ba ...

2020

A polymeric ionic liquid catalyst for the N-formylation and N-methylation of amines using CO2/PhSiH3

Paul Joseph Dyson, Andreas Züttel, Zhaofu Fei, Kyriakos Stylianou, Arunraj Chidambaram, Aswin Gopakumar, Dmitry Vasilyev, Serhii Shyshkanov

We describe a polymeric ionic liquid (PIL) derived from trimethyl(p-vinylbenzyl)ammonium chloride ([VBTAm]Cl) that efficiently catalyzes the N-formylation of amines employing CO2 and PhSiH3 at room temperature with low catalyst loadings in near-quantitativ ...

2020

Reactions of nitrogen-containing compounds with ozone: kinetics and mechanisms

Sung Eun Lim

Nitrogen-containing moieties are widespread in natural waters in dissolved organic nitrogen and micropollu-tants. They are often susceptible to an electrophilic attack of ozone because of the electron-rich nature of the neutral form of nitrogen in organic ...

EPFL2020

Catalyst Proximity-Induced Functionalization of h-BN with Quat Derivatives

Magalí Alejandra Lingenfelder, Bart Willem Stel, Gabriele Tocci, Huanyao Cun

Inert single-layer boron nitride (h-BN) grown on a catalytic metal may be functionalized with quaternary ammonium compounds (quats) that are widely used as nonreactive electrolytes. We observe that the quat treatment, which facilitates the electrochemical ...

2019

Palladium-Catalyzed Synthesis of Ketenimines from Isocyanides and Synthetic Studies Towards the Total Synthesis of Mersilongine

Mathias Mamboury

In the first chapter of this thesis, the development of two new reactions for the synthesis of vinyl ketenimines and alpha-oxo-ketenimines from isocyanides is presented. These palladium-catalyzed transformations both feature an isocyanide insertion / beta- ...

EPFL2019

Dual Photoredox/Copper Catalysis for the Remote C(sp3 )−H Functionalization of Alcohols and Alkyl Halides by N -Alkoxypyridinium Salts

Qian Wang, Jieping Zhu, Xu Bao

Under mild dual photoredox/copper catalysis, the reaction of N-alkoxypyridinium salts with readily available silyl reagents (TMSN3, TMSCN, TMSNCS) afforded d-azido, d-cyano, and d-thiocyanato alcohols in high yields. The reaction went through a domino proc ...

Wiley-VCH Verlag GmbH2019

Re-assessing the Formation of N-nitrosamines during Chloramination of Various Nitrogenous Compounds using Specific and Total N-nitrosamines Analysis

Urs von Gunten, Florian Frédéric Vincent Breider

N-nitrosamines (NOAs) are potent carcinogenic and mutagenic compounds that can be present in water, biological fluids, food, consumer products and cigarette smoke. Several studies have shown that the formation of NOAs in water can arise from the reactions ...

2018

Specific and total N -nitrosamines formation potentials of nitrogenous micropollutants during chloramination

Urs von Gunten, Florian Frédéric Vincent Breider, Caroline Gachet Aquillon

N-nitrosamines are a group of potent human carcinogens that can be formed during oxidative treatment of drinking water and wastewater. Many tertiary and quaternary amines present in consumer products (e.g., pharmaceuticals, personal care and household prod ...

2018

Mixed cation perovskite solid state solar cell and fabrication thereof

Michael Graetzel, Shaik Mohammed Zakeeruddin, Wolfgang Richard Tress, Michael Saliba, Konrad Domanski, Jiyoun Seo

A perovskite material including an organic-inorganic perovskite structure of formula (I), AnMX3 (I), n being the number of cation A and an integer >4, A being a monovalent cation selected from inorganic cations Ai and/or from organic cations Ao, M being a ...

2018

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

Selective Catalytic Reduction of NOx

Oliver Kröcher

The deactivation pathways of sulfonated carbon catalysts prepared from different carbons were studied during the aqueous‐phase hydrolysis of cellobiose under continuous‐flow conditions. The sulfonation of carbon materials with a low degree of graphitizatio ...

2018

Deactivation and Regeneration of Sulfonated Carbon Catalysts in Hydrothermal Reaction Environments

Oliver Kröcher, Frédéric Vogel

2018

Lattice Energy as Emerging General Parameter Describing Ionic Organic Semiconducting Materials Properties

Donatas Gesevicius

Cyanine dyes represent a class of ionic functional materials used by a broad heterogeneous science community contain-ing biologists, chemists, physicists and materials scientists. Their diverse application opportunities are ranging from fluorescence marker ...

EPFL2018