Through their electronic and steric properties, ligands play a crucial role in coordination chemistry, in particular in organometallic catalysis. They are able to influence the net electron density on the metallic center and can therefore drive its behavior and reactivity. To access the finest tuning of the catalytic reaction pathway, a detailed steric and electronic description of the ligands is required. A large variety of experimental methods have been developed
within the years, the most well-known being that developed by Tolman (Tolman Electronic Parameter). However, these approaches may suffer from some limitations, in particular in the detailed description of the electronic influence of the ligand. The ligand electronic interaction is indeed often rationalized using the Dewar-Chatt-Ducanson model which involves a σ-donor and a π-acceptor capability of the ligand. Most of the experimental methods give only
access to a global electronic effect but not to a detailed description of these two effects. We have recently developed a new experimental methodology aiming at measuring in details these effects. Our approach is based on mass spectrometry (MS) techniques and synchrotron radiation photoionization experiments. The proposed project will focus on the study of N-heterocyclic carbenes (NHC) ligands using these two methods. Since their discovery in the 90’s, these compounds are indeed employed in a very large variety of catalytic reactions due to their great versatility and easy preparation. We aim at improving the electronic description of these ligands in order to improve their tunability in catalytic reactions.
This project involves several teams with a large field of competences: organometallic synthesis, theory, MS, photoelectron spectroscopy. The PhD candidate will be interacting with all the partners and will be in charge of the MS and spectroscopic investigation of the HC-complexes.
The work will take place on two sites and will imply two research groups: the Organic and Biological Structural Chemistry (CSOB) group of the Parisian Institute of Molecular Chemistry (Sorbonne University, Paris) and the DESIRS beamline research group of the SOLEIL synchrotron facility center within the Paris-Saclay University cluster (Gif-sur-Yvette). The PhD candidate will have access to the mass spectrometers of the CSOB group (http://www.ipcm.fr/Presentation,278) and to the spectrometers of the DESIRS beamline (https://www.synchrotron-soleil.fr/en/beamlines/DESIRS). A researcher of each group will supervise the PhD candidate (Héloïse Dossmann at SU and Gustavo Garcia at SOLEIL).
The contract is planned to start in autumn 2019 for a 3 years duration and is fully founded (Labex/SOLEIL).
- Master degree in Physical Chemistry, Chemical Physics or Chemistry with a very strong
interest for the chemistry/physics interface.
- Very good communication and writing skills.
- First experience welcome in mass spectrometry or spectroscopy.
|Title||Fully-funded PhD fellowship offer - Experimental investigation of carbenes ligands electronic effects in organometallic complexes|
|Job location||L'Orme des Merisiers, 91190 Saint-Aubin|
|Published||January 29, 2020|
|Job types||PhD  |
|Fields||Catalysis,   Physical Chemistry,   Spectroscopy,   Chemical Physics,   Photonics  |