Publications associées à Reactive intermediate

Hypervalent Iodine: New Reagents and Functionalization of Peptides

Alkynes are found in a multitude of natural or synthetic bioactive compounds. In addition to the capacity of these chemical motifs to impact the physicochemical properties of a molecule of interest, the well-established reactivity of alkynes makes them ide ...

EPFL2023

Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states

Urs von Gunten, Joanna Maria Houska, Silvio Canonica, Stephanie Christa Remke

Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studie ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Synthesis and application of bifunctional hypervalent iodine reagents for peptide modification

Elija Grinhagena

Protein-protein interactions (PPIs) are responsible for regulating many biological processes in human bodies. PPIs often have a large binding site and often interact through an alpha helical segment. Therefore, the inhibition of PPIs can be difficult using ...

EPFL2023

Activation of aminocyclopropanes via radical intermediates

Jérôme Waser, Mingming Wang

Aminocyclopropanes are versatile building blocks for accessing high value-added nitrogen-containing products. To control ring-opening promoted by ring strain, the Lewis acid activation of donor-acceptor substituted systems is now well established. Over the ...

Royal Society of Chemistry2022

Organic Chemistry and Synthesis Rely More and More upon Catalysts

Pierre Vogel

A few months before the COVID-19 pandemic, Pierre Vogel and Kendall N. Houk published with a new textbook Wiley-VCH, "Organic Chemistry: Theory, Reactivity, and Mechanisms in Modern Synthesis", with a foreword from the late Roberts H. Grubbs. The book demo ...

MDPI2022

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Urs von Gunten, Silvio Canonica, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Chemo- and regio-divergent access to fluorinated 1-alkyl and 1-acyl triazenes from alkynyl triazenes

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

The 1,1,2,2-tetrafluoroethylene unit is prevalent in bioactive molecules and functional materials. Despite being in principle a straightforward strategy to access this motif, the direct tetrafluorination of alkynes involves very hazardous or inconvenient r ...

2022

Active sites on copper-based catalysts for electrochemical CO2 reduction selectively to C2+ products

Jie Zhang

Electrochemical CO2 reduction (eCO2RR) towards value-added chemicals, powered by renewable electricity, is a promising technology for storing the intermittent renewable energy in the form of chemical bonds. Among the various products of eCO2RR, multi-carbo ...

EPFL2022

New methods for structure determination and speciation by NMR crystallography

Martins Balodis

NMR crystallography has been around for half a century, but with the advent of NMR crystal structure determination protocols in the last decade it has shown perspectives that were not seen before. Amalgamation of NMR and crystal structure determination has ...

EPFL2022

Development of remote C-H bond functionalization of redox-active alcohol derivatives and oxidative transformations under photoredox catalysis

Alexandre Julien Florent Leclair

The development of radical-based remote C(sp3)-H functionalizations of redox-active alcohol derivatives, oxidative cycloaddition and rearrangement transformations under visible light photocatalysis constitute the basis of this thesis. The first chapter des ...

EPFL2021

Aqueous-phase reactive species formed by fine particulate matter from remote forests and polluted urban air

Andrea Mario Arangio, Ting Zhang, Jing Li

In the aqueous phase, fine particulate matter can form reactive species (RS) that influence the aging, properties, and health effects of atmospheric aerosols. In this study, we explore the RS yields of aerosol samples from a remote forest (Hyytiala, Finlan ...

Copernicus Publications2021

Colloidal Nanocrystals as Precursors and Intermediates in Solid State Reactions for Multinary Oxide Nanomaterials

Raffaella Buonsanti, Anna Loiudice, Valeria Mantella

Polyelemental compounds with dimensions in the nanosized regime are desirable in a large variety of applications, yet their synthesis remains a general challenge in chemistry. One of the major bottlenecks to obtaining multinary systems is the complexity of ...

2021

Intermolecular Pd(0)-Catalyzed Atropo-enantioselective C-H Arylation of Heteroarenes and Other Investigations into the Enantioselective Activation of Challenging C(sp3)-H Bonds

Qui-Hien Nguyen

The direct construction of stereogenic axes by enantioselective C-H arylation has been regarded as a very challenging transformation. Very few examples have been reported, despite the indisputable straight-forwardness of the methodology. This is due to the ...

EPFL2021

Isolation and characterization of diazoolefins

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

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

Stepwise Reduction of Dinitrogen by a Uranium-Potassium Complex Yielding a U(VI)/U(IV) Tetranitride Cluster

Marinella Mazzanti, Farzaneh Fadaei Tirani, Ivica Zivkovic, Luciano Barluzzi, Nadir Jori

Multimetallic cooperativity is believed to play a key role in the cleavage of dinitrogen to nitrides (N3-), but the mechanism remains ambiguous due to the lack of isolated intermediates. Herein, we report the reduction of the complex [K-2{[U-V(OSi((OBu)-Bu ...

2021

Engaging 1-Alkynyl Triazenes in Transition Metal-Catalyzed and Fluorinative Transformations

Jin Fay Tan

Triazenes have garnered great attention for their anti-cancer properties and versatility in organic chemistry. Recently, a novel synthesis of 1-alkynyl triazenes was reported. This thesis describes the compatibility, reactivity and applications of 1-alkyny ...

EPFL2021

Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

Jérôme Waser, Marion Marie-Agnès Garreau, Stephanie Grace Elizabeth Amos, Luca Buzzetti

Organic dyes have emerged as a reliable class of photoredox catalysts. Their great structural variety combined with the easy finetuning of their electronic properties has unlocked new possibilities for the generation of reactive intermediates. In this revi ...

2020

Synergistic Cu/CeO2 carbon nanofiber catalysts for efficient CO2 electroreduction

Andreas Züttel, Wen Luo, Jie Zhang

The electrochemical reduction of carbon dioxide (CO2RR) has attracted enormous interest because of the energy crisis and climate change; however, more efficient catalysts are required for practical applications. Herein, we present electrospinning as a faci ...

Elsevier2020

Computational Modeling of the Oxygen Evolution Reaction at Semiconductor-Water Interfaces: A Path Towards Breaking Linear Scaling Relationships

Patrick Gono

Photoelectrochemical water splitting is a promising source of clean, renewable fuel in the form of hydrogen. Despite extensive research endeavors, the widespread adoption of this technology is impeded due to suboptimal catalysts for the oxygen evolution re ...

EPFL2020

Polymer Lamellae as Reaction Intermediates in the Formation of Copper Nanospheres as Evidenced by In Situ X-ray Studies

Raffaella Buonsanti, Dragos-Constantin Stoian, Valeria Mantella, James Richard Pankhurst, Chethana Janardhana Gadiyar, Michal Stanislaw Strach, Kilian Frank

The classical nucleation theory (CNT) is the most common theoretical framework used to explain particle formation. However, nucleation is a complex process with reaction pathways which are often not covered by the CNT. Herein, we study the formation mechan ...

Wiley-VCH Verlag GmbH2020