Publications associées à Cu-Catalyzed Photoredox Chlorosulfonation of Alkenes and Alkynes

Reactivity of Bromine Radical with Dissolved Organic Matter Moieties and Monochloramine: Effect on Bromate Formation during Ozonation

Bromine radical (Br center dot) has been hypothesized to be a key intermediate of bromate formation during ozonation. Once formed, Br center dot further reacts with ozone to eventually form bromate. However, this reaction competes with the reaction of Br c ...

AMER CHEMICAL SOC2023

A Cobalt Nanocatalyst for the Hydrogenation and Oxidative Dehydrogenation of N-heterocycles

Paul Joseph Dyson, Yelin Hu, Matthias Beller, Mingyang Liu, Xiang Li

Catalytic hydrogenation and oxidative dehydrogenation of N-heterocycles to produce tetrahydroquinoline and quinoline derivatives are important reactions of particular importance in the agrochemical and pharmaceutical industries. Herein, we report earth-abu ...

Wiley-VCH Verlag2023

Isolation and characterization of diazoolefins

Kay Severin, Rosario Scopelliti, Farzaneh Fadaei Tirani, Paul Varava, Zhaowen Dong

Diazoolefins tend to be highly reactive compounds that rapidly lose dinitrogen. So far, most experimental evidence for diazoolefins is indirect, via trapping experiments. Here we show that diazoolefins are observed to form in reactions of N-heterocyclic ol ...

2021

Amphiphilic Iodine(III) Reagents for the Lipophilization of Peptides in Water

Jérôme Waser, Durga Prasada Rao Hari, Romain Gaëtan Tessier, Abhaya Kumar Mishra

We report the functionalization of cysteine residues with lipophilic alkynes bearing a silyl group or an alkyl chain using amphiphilic ethynylbenziodoxolone reagents (EBXs). The reactions were carried out in buffer (pH 6 to 9), without organic co-solvent o ...

Wiley-VCH Verlag GmbH2021

Copper(I) Based Photoredox Chemistry

Murat Alkan

Photoredox catalysis has become a powerful tool for chemists. However, the reliance on expensive Ir and Ru based photoredox catalysts (PC) motivates research for more sustainable options. Copper complexes based on favorable photophysical properties, high a ...

EPFL2020

SET processes in Lewis acid–base reactions: the tritylation of N-heterocyclic carbenes

Andrzej Sienkiewicz, Kay Severin, Rosario Scopelliti, Cristian Pezzato, Farzaneh Fadaei Tirani, Zhaowen Dong

Reactions between N-heterocyclic carbenes (NHCs) and the trityl cation, [Ph3C]+, give covalent adducts of type [NHC–CPh3]+ and/or [NHC–C6H5–CPh2]+. EPR spectroscopy, UV-Vis analyses, and trapping experiments imply that adduct formation involves carbene rad ...

2020

Mechanisms of the Heterogeneously Catalyzed Reaction of CO2 Hydrogenation on Transition Metal Surfaces

Kun Zhao

Renewable energy supply and energy storage in a closed materials cycle are the urgent global challenges of the 21st century. Carbon dioxide (CO2) hydrogenation over catalysts is a method to produce synthetic fuels from renewable energy in a CO2 neutral cyc ...

EPFL2020

Exploring Perovskite-Metal Nanoassemblies for Photocatalytic Applications

Seryio Saris

The development of sustainable, renewable and economic chemical processes lies in the centre of todayâ s global energy challenge. Like in plants, artificial photosynthesis offers an auspicious solution in harvesting solar energy and storing it in chemical ...

EPFL2020

Molecular Engineering of Electrode Surfaces for Electrocatalysis

Patrick Eduard Alexa

Electrocatalysts play an important part on the route towards environmental friendly energy sources. They support modern technologies like fuel cells to move further away from the utilization of fossil fuels and the resulting CO2 emission into our atmospher ...

EPFL2020

Organocatalysts in C-N Bond Forming Reactions of Amines with CO2

Martin Hulla

The thesis describes a simple approach for N-formylation of amines with CO2 and hydrosilane reducing agents, the use of organic salts as N-formylation catalysts, their physical properties required for high catalytic activity and their role in the catalytic ...

EPFL2019

Investigation of the heterogeneously catalysed gas phase CO2 hydrogenation reaction: Development of analysis methods and reaction analysis on pristine metal catalysts

Robin Tobias Andreas Mutschler

The aim of this thesis is to contribute to the development of analysis methods that enable an improved investigation of the CO2 hydrogenation reaction such as quantitative mass spectrometry and infrared thermography. Furthermore, the contribution is in the ...

EPFL2019

CO2 hydrogenation reaction over pristine Fe, Co, Ni, Cu and Al2O3 supported Ru: Comparison and determination of the activation energies

Andreas Züttel, Robin Tobias Andreas Mutschler, Wen Luo, Noris André Gallandat, Emanuele Moioli

Fe, Co, Ni and Cu are the main non-noble industrially significant catalysts in the CO2 and CO gas phase hydrogenation reaction towards hydrocarbons and alcohols. These catalysts are typically supported on metal oxides such as SiO2, TiO2, Al2O3 and ZnO, in ...

ACADEMIC PRESS INC ELSEVIER SCIENCE2018

Water Oxidation Kinetics of Accumulated Holes on the Surface of a TiO2 Photoanode: A Rate Law Analysis

Florian Le Formal, Min Ling, Yimeng Ma

It has been more than 40 years since Fujishima and Honda demonstrated water splitting using TiO2, yet there is still no clear mechanism by which surface holes on TiO2 oxidize water. In this paper, we use a range of complementary techniques to study this re ...

Amer Chemical Soc2017

Atomic Scale Observation of Chemical and Electronic Properties of Metal-Oxide Surfaces

Christian Alexander Stephan Dette

To meet the future global energy demand - an estimated additional 10 terawatts (TWs) per year in 2050 - a diversification of energy sources and fuels is needed. Solar energy represents a prominent alternative energy source. An important material for these ...

EPFL2016

Organocatalysis: Fundamentals and Comparisons to Metal and Enzyme Catalysis

Pierre Vogel

Catalysis fulfills the promise that high-yielding chemical transformations will require little energy and produce no toxic waste. This message is carried by the study of the evolution of molecular catalysis of some of the most important reactions in organi ...

2016

Mechanism of oxygen reduction by metallocenes near liquid|liquid interfaces

Hubert Girault, Haiqiang Deng, Thomas James Stockmann, Pekka Eero Peljo

The mechanism of the oxygen reduction reaction (ORR) at a liquid|liquid interface, employing ferrocene (Fc) derivatives – such as decamethylferrocene (DMFc) – as a lipophilic electron donor along with sulfuric acid as an aqueous proton source, was elucidat ...

Elsevier2014

Electrochemical oxygen reduction at soft interfaces catalyzed by the transfer of hydrated lithium cations

Hubert Girault, Haiqiang Deng, Thomas James Stockmann, Pekka Eero Peljo

The oxygen reduction reaction by decamethylferrocene (DMFc), triggered by hydrophilic metallic cations behaving as Lewis acids towards water molecules in a homogeneous organic phase reaction, was investigated using cyclic voltammetry at the water|1,2-dichl ...

Elsevier2014

Compact reactor for continuous multi-phase reactions : solvent-free alkyne hydrogenation as a case study

Martin Grasemann

The objective of this thesis is the development of a compact reactor for continuous three-phase reactions in single-pass configurations. The design is based on a bubble column reactor staged with layers of catalytic material. To make the reactor suitable f ...

EPFL2009

Effect of Lewis acids on the Diels-Alder reaction in ionic liquids with different activation modes

Paul Joseph Dyson, Ana Vidis

The Diels-Alder reaction has been examd. in room temp. ionic liqs. with high molar concns. of Lewis acids under various conditions. A molar ratio of 10% catalyst gave a large increase in the selectivity and the yield of the reaction. The effect of catalyst ...

2008

Study of N2O decomposition over Fe-ZSM-5 with transient methods

Petra Prechtl

Nitrous oxide is the third most important gas contributing to global warming and its concentration in the atmosphere is still on the rise. Nitric acid production represents the largest source of N2O in the chemical industry, with a total annual emission of ...

EPFL2007