PhD offer (CSOB/CHEMBIO group) – Rationalizing organometallic complexes activity using a combined mass spectrometry, action spectroscopy and theoretical approach

The CSOB and CHEMBIO groups are looking for a candidate for a PhD scholarship on the topic:

Rationalizing organometallic complexes activity
using a combined mass spectrometry,
action spectroscopy and theoretical approach

Project overview :  

In the last decades, Au complexes have been investigated over a large range of applications including catalysis, biological applications and photophysics. Gold catalysis relies on the Lewis acidity of gold to activate unsaturated bonds toward nucleophilic attacks. As such, it requires the direct coordination of the unsaturated substrate on the gold cation and implies the generation of a vacant coordination site on gold by decoordination of a ligand. This feature underlines the crucial interest of estimating the Au-ligand strength in order to rationalize and optimize catalytic properties of gold complexes. Furthermore, organometallic gold complexes have also attracted an increasing interest to circumvent the limitation of platinum-based drugs used as chemotherapeutics for various types of cancer since the FDA approval of cis-diamminodichloroplatinum(II) (cisplatin) in the late 70’s. However, while the direct binding of platinum-based drugs to the imidazole moiety of puric bases of DNA is recognized as their main mode of action, Au binding to DNA is weak, reversible and is recognized to have only a poor involvement in gold anticancer mechanism. The Au-ligand bonding thus appears as a crucial parameter that needs to be evaluated in order to rationalize the reactivity as a catalyst as well as the anti-cancer activity of AuIII complexes. In the literature, several works have aimed to describe ligand effects on Au complexes, but most of them focused on AuI and more rarely on AuIII. To date, none of them was able to rationalize the Au/Pt activity difference.

Our consortium has been working for several years now on developing a full experimental and theoretical strategy devoted to the exploration of metal-ligand interaction including synthesis of the ligands and the complexes of interests, study of their gas-phase dissociation using mass spectrometry and the development of adequate kinetic and theoretical models and rationalization of the catalytic or biological activity of the studied complexes by means of the metal-ligand bond strength. With this PhD project, we wish to go a step further and 1) understand the activity difference between Pt and Au complexes by means of fundamental parameters such as ligand bonding strength including σ-bonding or π-backdonation properties and 2) develop a new methodology to determine thermochemical parameters based on UV action spectroscopy coupled to mass spectrometry.

The PhD candidate will be in charge of this project and will have the opportunity to work on all aspects of the projects as organometallic synthesis, mass spectrometry (incl. kinetic modelling), electronic structure calculations, action spectroscopy.

Consortium and working environment

The project supervision implies two teams of the Institut Parisien de Chimie Moléculaire at Sorbonne Université in Paris : the Chimie Structurale Organique et Biologique team (CSOB) with Héloïse Dossmann (Associate Pr.) and Denis Lesage (Research Engineer) and the ChemBio team with Benoit Bertrand (CNRS researcher). H. Dossmann and D. Lesage are physical chemists specialized in gas-phase chemistry in particular in the determination of thermochemical parameters using mass spectrometry and electronic structure calculations. B. Bertrand is chemist specialist of organometallic synthesis, bioconjugation and biological investigations of compounds.

The PhD candidate will join the Institut Parisien de Chimie Moléculaire and will also have the opportunity to work with our collaborator, Luke MacAleese in Lyon, specialized in action spectroscopy.

Profiles : 

We are looking for a candidate with a strong scientific curiosity and interest in many fields of chemistry, able to teamwork and communicate with several scientists. With this PhD project, the candidate will have the possibility to develop multi skills in organometallic synthesis, mass spectrometry, spectroscopy, kinetic modelling, quantum chemistry calculations and biological activity testing. He/she will be seconded by the consortium member for all these tasks and will be free to orientate his/her work depending on his/her background and predilection; the expected basis, however, is mass spectrometry work.

Expected academic background and experience
–  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 in mass spectrometry or spectroscopy and/or gas-phase chemistry will be positively considered.

Duration:

36 months from October 2024

Application:

– Send a cover letter
– and a CV (including the name of 2 or 3 referees)

Keywords: gas-phase chemistry, mass spectrometry, organometallic complexes, metal-ligand interaction, instrumentation, thermochemical data measurements, DFT, kinetic modeling (RRKM), synthesis, UV spectroscopy photodissociation