PhD contract (H/F) -Synthesis of new heptazines for photocatalysis, both homogeneous and on grafted...

As a chemistry laboratory within ENS Paris-Saclay, the PPSM's activities focus on the research and study of molecules and materials that can be stimulated by photo-induced phenomena, the action of electrons, sensitivity to the presence of ions or biological activity, and which are integrated into problems related to the environment, health and information technologies.
In this context, the material resources and skills of different chemical specialities are brought together at the PPSM, making it possible to carry out several facets of the work that chemists must do: design (molecular engineering), synthesis of molecules, manufacture of materials and study of properties.
The members of the PPSM are positioned in the scientific research community on a national and international scale, contributing to the advancement of fundamental knowledge in its core areas of expertise: photochemistry, fluorescence, spectroscopy, electrochemistry, nanomaterials, molecular recognition, organic synthesis.

This thesis subject is part of the Hepta-cat project, funded by the ANR over the period 2021-2025, whose objective is to develop and study new heptazines, then to apply them as photocatalysts, in the homogeneous phase and via grafted materials. Indeed, heptazines are nitrogenous heterocycles, still little studied, which present promising photophysical (long-lived fluorescence) and electrochemical properties.
The objective of the thesis will be to develop synthetic routes to obtain new heptazines and to study the electrochemical and fluorescence properties of the resulting compounds. The most efficient heptazines (high reduction potential, long fluorescence lifetime) will be used in photocatalysed reactions, which will be developed in the team of Dr. Géraldine Masson (ICSN, Gif-sur-Yvette), which is a partner in the project. Our main synthon will be the newly discovered tris(diethylpyrazolyl)heptazine, or TDPH. However, in order to prepare new perfluorinated derivatives of great interest, alkoxyheptazines prepared from TDPH will in turn be considered as potential starting materials.
Another related part of the project, in partnership with Dr. F. Rossignol (Institut IRCER, Univ. de Limoges), also consists of producing graftable heptazines on silica supports. We plan to prepare, for example, heptazine derivatives monosubstituted by a 3-aminopropyltriethoxysilane chain.
The scientific direction will be ensured by Pr Pierre Audebert, Dr Clémence Allain and Dr Laurent Galmiche in the PPSM laboratory of ENS Paris Saclay (Gif-sur-Yvette), and could start on November 1st, 2021.