The team, of roughly ten researchers, is built around three permanent staff : Dr. Nicolas Mézailles (Research Director DR2 CNRS and “Professeur Chargé de Cours” at the Ecole Polytechnique, Palaiseau), Dr. Noel Nebra-Muñiz (Assistant professor: CR2 CNRS) and Dr. Marie Boutignon (Assistant professor, Université P. Sabatier, Toulouse). The three research themes currently developed in the group, as our name suggests, are linked to the studies (synthesis and reactivity) of high energy species, ranging from metal complexes to main group species of “high energy”. Or goals are manifold and relate to:
Novel synthetic strategies toward carbene complexes, and applications
This first theme is based on the specific properties of heteroelements, such as phosphorus, which allow us to stabilze key species, highly reactive, of our strategy: geminal dianions. The intimate understanding of the parameters that permit the stabilization of two charges on the same C center is achieved both experimentally and via DFT Calculations.
During the past years, we have thus been able to develop a range of stable geminal dianions, which ha. ve in turn lead to the synthesis of carbene complexes for very diverse metal centers ranging from U(IV) and U(VI) to late transition metal centers (Pd(II)). Thanks to this approach, the reactivity of the M=C bond can be modulated very precisely.
Synthesis and reactivity of unsaturated metal fragments
The goals of this second research theme are centered on organometallic chemistry. It is our aim to develop synthetic strategies leading to the generation of unsaturated metal fragments under mild conditions, key to increased reactivity. Applications are diverse, ranging from catalysis (CC bond formation) to activations of inert bonds or molecules (CH bond activation or N2 functionalization). In order to achieve our goals, a dual approach is used involving experience and theoretical calculations. Transition metal fragments « M(L2) » (with M = group 10 metal, and L2 = bidentate ligand), or « M(L4) » (M = group 6 or 8, and L4 = tetradentate ligand).
Reactivity of white phosphorus, P4, toward metallic systems (transition metal complexes and/or metal nanoparticles)
The basic molecule in phosphorus chemistry is P4, white phosphorus. It is quite a fascinating molecule, simply kept under water but which burns in air. Historically, this molecule has been used to make matches. Unlike many other molecules which have to be activated to react, the difficulty here resides in controlling the reactivity of P4. Two approaches are developed in our group. Firstly, we design transition metal fragments which will allow the controlled transformation of P4 into diverse Pn fragments (n=1, 2 or 3) which will be subsequently functionalized. The second approach takes profit of the high reactivity of P4 to transfer at once all 4 P atoms to a given substrate. We have thus developed a novel and efficient access to nanoparticles of metal-phosphides via the reaction of stoichiometric amounts of P4 and metal nanoparticles.
These research themes are supported not only by the CNRS and Université Paul Sabatier, but also by national and international programs (ANR, European program « ITN SUSPHOS », Merlion program with Singapour). We also develop a partnership with the IFPEN (Institut Français du Petrole, Energies Nouvelles). Finally, our team has been awarded by the « Région Midi-Pyrénées »: « création d’équipes d’excellence en Région Midi-Pyrénées » (creation of research teams of excellence in the “Région Midi-Pyrénées”).
Research work lead within the team lead to the fundation of the SWAN-H start-up, which remains associated with the SHEN team and is hosted by the MRV (Maison de la Recherche et de la Valorisation) of the Toulouse-Midi-Pyrénées Federal University