Publications associées à Associative substitution

The Mononuclear Metal-Binding Site of Mo-Nitrogenase Is Not Required for Activity

The biological N-2-fixation process is catalyzed exclusively by metallocofactor-containing nitrogenases. Structural and spectroscopic studies highlighted the presence of an additional mononuclear metal-binding (MMB) site, which can coordinate Fe in additio ...

Amer Chemical Soc2023

Murunskite - a new class of functional material

Davor Tolj

The subject of the present work is discovery and in-depth characterization of a new class of functional materials. Tuning of the bond polarity and orbital occupation with a goal of establishing balance between localization and delocalization of electrons - ...

EPFL2023

CO2 Capture and Release in Amine Solutions: To What Extent Can Molecular Simulations Help Understand the Trends?

Wanda Andreoni, Fabio Pietrucci, Changru Ma

Absorption in amine solutions is a well-established advanced technology for CO2 capture. However, the fundamental aspects of the chemical reactions occurring in solution still appear to be unclear. Our previous investigation of aqueous monoethanolamine (ME ...

2023

Diamine Synthesis via the Nitrogen-Directed Azidation of sigma- and pi-C-C Bonds

Jérôme Waser, Mingming Wang

Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. ...

2021

Understanding How Ligand Functionalization Influences CO2 and N-2 Adsorption in a Sodalite Metal-Organic Framework

Michele Ceriotti, Wendy Lee Queen, Pascal Alexander Schouwink, Mehrdad Asgari, Olga Trukhina, Ilia Kochetygov, Rocio Semino Barbaresi

In this work, a detailed study is conducted to understand how ligand substitution influences the CO, and N-2 adsorption properties of two highly crystalline sodalite metal-organic frameworks (MOFs) known as Cu-BTT (BTT-3 = 1,3,5-benzenetristetrazolate) and ...

AMER CHEMICAL SOC2020

Principal Descriptors of Ionic Liquid Co-catalysts for the Electrochemical Reduction of CO2

Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Serhii Shyshkanov, Dmitry Vasilyev, Erfan Shirzadi

Electrochemical reduction of carbon dioxide (CO2RR) is promoted by ionic liquid (IL) co-catalysts, and several mechanisms have been proposed to explain their role. Due to the complexity of the CO2RR and the limited number of active IL co-catalysts, a conse ...

AMER CHEMICAL SOC2020

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

Getting the Right Grip? How Understanding Electrophile Selectivity Profiles Could Illuminate Our Understanding of Redox Signaling

Yimon Aye, Lingxi Wang

Recent Advances: Herein, we focus on the first step of this process, electrophile sensing. Electrophile sensing is typically a deceptively simple reaction between the thiol of a protein cysteine, of which there are around 200,000 in the human proteome, and ...

MARY ANN LIEBERT, INC2020

Development of Site-Specific Mg2+-RNA Force Field Parameters: A Dream or Reality? Guidelines from Combined Molecular Dynamics and Quantum Mechanics Simulations

Ursula Röthlisberger, Giulia Palermo, Lorenzo Casalino

The vital contribution of Mg2+ ions to RNA biology is challenging to dissect at the experimental level. This calls for the integrative support of atomistic simulations, which at the classical level are plagued by limited accuracy. Indeed, force fields intr ...

2017

Quantum Chemical Study of the Water Exchange Mechanism of the Americyl(VI) Aqua Ion

François Rotzinger, Alberto Fabrizio

The water exchange reaction of the americyl(VI) aqua ion was investigated with quantum chemical methods, density functional theory (DFT), and wave function theory (WFT). Associative and dissociative substitution mechanisms were studied, whereby DFT produce ...

American Chemical Society2016

Water Exchange on [Ln(DO3A)(H2O)2] and [Ln(DTTA–Me)(H2O)2]− Studied by Variable Temperature, Pressure, and Magnetic Field NMR

Lothar Helm, Shima Karimi

Water exchange kinetics of [Ln(L)(H2O)2]x complexes (Ln = Pr, Nd, Dy, Tm, and Yb; L = DO3A and DTTA–Me) were studied by 17O NMR spectroscopy as a function of temperature, pressure, and frequency and by 1H nuclear magnetic relaxation dispersion. Water excha ...

American Chemical Society2016

Complexation of [Gd(DTTA–Me)(H2O)2]− by Fluoride and Its Consequences to Water Exchange

Lothar Helm, Loïck Moriggi, Shima Karimi, Gail Ruth Hunter

The displacement of water molecule(s) from the inner coordination sphere of [Gd(DTTA–Me)(H2O)2]− (DTTA = ethylenetriamine-N,N,N″,N″-tetraacetate) by fluoride has been studied by multinuclear NMR relaxation (1H, 17O, 19F) and DFT calculations. Fluoride anio ...

American Chemical Society2016

Water exchange studies of lanthanide complexes and aqua ions

Shima Karimi

Complexes of lanthanide (III) ions have been used in structural studies of biomolecules and as contrast agents (CA). Clinically approved CAs have only one water molecule in their first coordination sphere. Structure and water exchange rate of these complex ...

EPFL2016

Evaluation of Water Exchange Kinetics on [Ln(AAZTAPh–NO2)(H2O)q]x Complexes Using Proton Nuclear Magnetic Resonance

Lothar Helm, Shima Karimi

Water exchange kinetics on [Ln(AAZTAPh–NO2)(H2O)q]− (Ln = Gd3+, Dy3+, or Tm3+) were determined by 1H nuclear magnetic resonance (NMR) measurements. The number of inner-sphere water molecules was found to change from two to one when going from Dy3+ to Tm3+. ...

American Chemical Society2016

Investigation of the water exchange mechanism of the Plutonyl(VI) and Uranyl(VI) ions with quantum chemical methods

François Rotzinger, Antonio Prlj

The water exchange reactions of PuO2(OH2)(5) and UO2(OH2)(5) were investigated with density functional theory (DFT) and wave function theory (WFT). Geometries and vibrational frequencies were calculated with DFT and CPCM hydration. The electron ...

Taylor & Francis2015

Catalytic Applications and Mechanistic Investigations of Iron Bis(oxazolinylphenyl)amino Pincer Complexes in Kumada Cross Coupling and Hydrosilylation Reactions

Gerald Bauer

The aim of the project was to investigate iron bis(oxazolinylphenyl)amino (bopa) pincer complexes as pre-catalysts in the enantioselective Kumada cross-coupling of non-activated alkyl halides with aryl Grignard reagents. From this preliminary cross-couplin ...

EPFL2015

Structure and Properties of the Precursor/Successor Complex and Transition State of the CrCl2+/Cr2+ Electron Self-Exchange Reaction via the Inner-Sphere Pathway

François Rotzinger

The electron self-exchange reaction CrCl(OH2)5(2+) + Cr(OH2)6(2+) -> Cr(OH2)(6)(2+) + CrCl(OH2)(5)(2+), proceeding via the inner-sphere pathway, was investigated with quantum-chemical methods. Geometry and vibrational frequencies of the precursor/successor ...

American Chemical Society2014

Electrochemically Controlled Proton-Transfer-Catalyzed Reactions at Liquid-Liquid Interfaces: Nucleophilic Substitution on Ferrocene Methanol

Hubert Girault, Liang Qiao, Pekka Eero Peljo

The generation of α-ferrocenyl carbocations from ferrocenyl alcohols for SN1 substitution at the water–organic solvent interface is initiated by the transfer of protons into the organic phase. The proton flux, and hence the reaction rate, can be controlled ...

Wiley-Blackwell2013

Cobalt Electrolyte/Dye Interactions in Dye-Sensitized Solar Cells: A Combined Computational and Experimental Study

Michael Graetzel, Mohammad Khaja Nazeeruddin, Jun Ho Yum, Filippo de Angelis

We report a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO2 surfaces sensitized by :ruthenium and organic dyes, and their impact on. the performance of the correspon ...

American Chemical Society2012

Pyridine-Based Lanthanide Complexes Combining MRI and NIR Luminescence Activities

Lothar Helm, Eva Jakab Toth, Jian Zhang, Sandrine Villette

A series of novel triazole derivative pyridine-based polyaminopolycarboxylate ligands has been synthesized for lanthanide complexation. This versatile platform of chelating agents combines advantageous properties for both magnetic resonance (MR) and optica ...

2012