• Bienvenue au DCM

    Le Département de Chimie Moléculaire de Grenoble est une unité mixte de recherche (UMR-5250) associant le CNRS et l’Université Grenoble Alpes. Créé le 01 Janvier 2007 par le regroupement des unités LEDSS (UMR-5616) et LEOPR (UMR-5630), le DCM mobilise environ 150 personnes autour de deux axes de recherches interactifs qui sont la chimie pour la santé et la chimie pour les nanosciences.

  • BEA

    Biosystèmes Electrochimiques et Analytiques

  • I2BM

    Ingénierie et Interactions BioMoléculaires

  • Chimie Inorganique Redox

    CIRE laboratory develops its research in the fields of molecular electrochemistry and redox photochemistry. We design molecular architectures with diverse functionalities often inspired by a bio-mimetic approach. Our work is directed towards both fundamental research(switchable systems, artificial photosynthesis, metal-radical coupling) and practical applications (nano-chemical devices, inhibitors development).

  • SeRCO

    Synthèse et Réactivité en Chimie Organique

  • Spectrométrie, Interactions, Chimie Théorique

    Expertise in the field of theoretical chemistry and experimental mass spectrometry :
    At the upper right, study of alkynes activation by Au(I) complexes with the help of Mass spectrometry; At the bottom in the left, TD-DFT development for the photochemistry ; At the bottom in the middle QM/MM Studies of Tyrosinase inhibitors ; At the right modelization of the reactivity in solution 

1/

Agenda

ZOOM

ZOOM O2 Activation by Non-Heme Thiolate-Based Dinuclear Fe Complexes
Iron centers featuring thiolates in their metal coordination sphere (as ligands or substrates) are well-known to activate dioxygen. Both heme and non-heme centers that contain iron-thiolate bonds are found in nature. Investigating the ability of iron–thiolate model complexes to activate O2 is expected to improve the understanding of the key factors that direct reactivity to either iron or sulfur. We report here the structural and redox properties of a thiolate-based dinuclear Fe complex, [FeII2(LS)2] (LS2– = 2,2′-(2,2′-bipyridine-6,6′-iyl)bis(1,1-diphenylethanethiolate)), and its reactivity with dioxygen, in comparison with its previously reported protonated counterpart, [FeII2(LS)(LSH)]+. When reaction with O2 occurs in the absence of protons or in the presence of 1 equiv of proton (i.e., from [FeII2(LS)(LSH)]+), unsupported μ-oxo or μ-hydroxo FeIII dinuclear complexes ([FeIII2(LS)2O] and [FeIII2(LS)2(OH)]+, respectively) are generated. [FeIII2(LS)2O], reported previously but isolated here for the first time from O2 activation, is characterized by single crystal X-ray diffraction and Mössbauer, resonance Raman, and NMR spectroscopies. The addition of protons leads to the release of water and the generation of a mixture of two Fe-based “oxygen-free” species. Density functional theory calculations provide insight into the formation of the μ-oxo or μ-hydroxo FeIII dimers, suggesting that a dinuclear μ-peroxo FeIIIintermediate is key to reactivity, and the structure of which changes as a function of protonation state. Compared to previously reported Mn–thiolate analogues, the evolution of the peroxo intermediates to the final products is different and involves a comproportionation vs a dismutation process for the Mn and Fe derivate, respectively.