Electrochemical study of the role of a H-bridged, unsymmetrically disubstituted diiron complex in proton reduction catalysis

Autor: Frédéric Gloaguen, Jean-François Capon, Nicolas Dumontet, Salah Ezzaher, Jean Talarmin, François Y. Pétillon, Philippe Schollhammer
Přispěvatelé: Chimie, Electrochimie Moléculaires et Chimie Analytique (CEMCA), Université de Brest (UBO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)
Rok vydání: 2009
Předmět:
Zdroj: Journal of Electroanalytical Chemistry
Journal of Electroanalytical Chemistry, Elsevier 2009, 626 (1-2), pp.161-170. ⟨10.1016/j.jelechem.2008.12.005⟩
ISSN: 1572-6657
DOI: 10.1016/j.jelechem.2008.12.005
Popis: The electrochemical behaviour of the unsymmetrically disubstituted [Fe 2 (CO) 4 (κ 2 -dppe)(μ-pdt)(μ-H)] + ( 1μH + ) complex was studied by cyclic voltammetry (CV) in MeCN– and CH 2 Cl 2 –[NBu 4 ][PF 6 ] both in the absence and in the presence of acid (HBF 4 · Et 2 O or HOTs). In the absence of acid, 1μH + undergoes a reversible one-electron oxidation and two-successive one-electron reductions, the first of which is partially reversible. In contrast to symmetrical analogues, 1μH + does not regenerate its neutral precursor 1 upon reduction on the CV timescale. When acid is present, the reduction leads to catalytic proton reduction at a mild potential (ca. −1.3 V vs. Fc + /Fc) according to an original mechanism where 1μH + is the catalyst. A second proton reduction process at −1.5 V is also observed for both HBF 4 · Et 2 O and HOTs. The latter is proposed to be catalysed by the one-electron reduced form of the H-bridged complex, 1μH .
Databáze: OpenAIRE