title: Deprotonation in Mixed-Valent Diiron(II,III) Complexes with Aniline or Benzimidazole Ligands.
abstract: We have previously investigated cis/trans isomerization processes in phenoxido-bridged mixed-valent Fe(II)Fe(III) complexes that contain either one aniline or one anilide ligand. In this work, we compare the properties of similar complexes bearing one terminal protic ligand, either aniline or 1H-benzimidazole. Whatever the ligand, (1)H NMR spectroscopy clearly evidences that the complexes are present in CH3CN as a mixture of cis- and trans-isomers in a close to 1:1 ratio. We show here that addition of NEt3 indeed allows the deprotonation of these ligands, the resulting complexes bearing either anilide or benzimidazolide that are coordinated to the ferric site. The latter are singular examples of a high-spin ferric ion coordinated to a benzimidazolide ligand. Whereas the trans-isomer of the anilide complex is the overwhelming species, benzimidazolide species are mixtures of cis- and trans-isomers in equal proportions. Moreover, cyclic voltammametry studies show that Fe(III)Fe(III) complexes with 1H-benzimidazole are more stable than their aniline counterparts, whereas the reverse is observed for the deprotonated species.
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Gouré
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Michaël
authors.initials: M
authors.lastname: Carboni
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.|‡CNRS, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Angélique
authors.initials: A
authors.lastname: Troussier
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Dubourdeaux
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.|§Univ. Grenoble Alpes, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Martin
authors.initials: M
authors.lastname: Clémancey
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.|‡CNRS, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Gon
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.|‡CNRS, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Ramachandran
authors.initials: R
authors.lastname: Balasubramanian
authors.affiliation: ∥CEA, INAC-SCIB-RICC, 38054 Grenoble, France.|⊥Univ. Grenoble Alpes, INAC-SCIB-RICC, 38054 Grenoble, France.
authors.forename: Colette
authors.initials: C
authors.lastname: Lebrun
authors.affiliation: ∥CEA, INAC-SCIB-RICC, 38054 Grenoble, France.|⊥Univ. Grenoble Alpes, INAC-SCIB-RICC, 38054 Grenoble, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Pécaut
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.|‡CNRS, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Blondin
authors.affiliation: †CEA, iRTSV-LCBM-pmb, 17 rue des Martyrs, 38054 Grenoble, France.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Latour