A Bioinspired Molybdenum Complex as a Catalyst for the Photo- and Electroreduction of Protons

Jean-Philippe Porcher (1) , Thibault Fogeron (1) , Maria Gomez-Mingot (1) , Etienne Derat (2) , Lise-Marie Chamoreau (2) , Yun Li (3) , Marc Fontecave (1)

1 Collège de France - Chaire Chimie des processus biologiques
2 IPCM - Institut Parisien de Chimie Moléculaire
3 Swinburne University of Technology [Melbourne]

A molybdenum-dithiolene-oxo complex was prepared as a model of some active sites of Mo/W-dependent enzymes. The ligand, a quinoxaline-pyran-fused dithiolene, mimics molybdopterin present in these active sites. For the first time, this type of complex was shown to be active as a catalyst for the photoreduction of protons with excellent turnover numbers (500) and good stability in aqueous/organic media and for the electroreduction of protons in acetonitrile with remarkable rate constants (1030 s(-1) at -1.3V versus Ag/AgCl). DFT calculations provided insight into the catalytic cycle of the reaction, suggesting that the oxo ligand plays a key role in proton exchange. These results provide a basis to optimize this new class of H-2-evolving catalysts.

Mots clés: density functional calculations; dithiolene ligands; homogeneous catalysis; hydrogen evolution reaction; molybdenum

Domaines: Chimie organique

Jean-Philippe Porcher, Thibault Fogeron, Maria Gomez-Mingot, Etienne Derat, Lise-Marie Chamoreau, et al.. A Bioinspired Molybdenum Complex as a Catalyst for the Photo- and Electroreduction of Protons. Angewandte Chemie International Edition, 2015, 54 (47), pp.14090-14093. ⟨10.1002/anie.201505607⟩. ⟨hal-01397965⟩