Ligand effects on the electrochemical behavior of [Fe2(CO)5(L){μ-(SCH2)2(Ph)P[double bond, length as m-dash]O}] (L = PPh3, P(OEt)3) hydrogenase model complexes

Abstract : In this paper we study the influence of substituting one CO ligand in [Fe2(CO)6{μ-(SCH2)2(Ph)P[double bond, length as m-dash]O}] (1) by better σ-donor L ligands affording [Fe2(CO)5(L){μ-(SCH2)2(Ph)P[double bond, length as m-dash]O}] {L = PPh3 (2) and P(OEt)3 (3)} in relation to the steric interactions and the voltammetric behavior. Cyclic voltammetric investigations under N2 and CO showed remarkable differences in the electrochemical behaviour of complexes 2 and 3: (i) Complex 2 tends to expel PPh3 upon reduction whereas complex 3 exhibits chemical reversibility and (ii) Under CO, complex 3 reacts with CO affording a new compound P, which shows a reversible wave at E1/2 ∼ −0.9 V (vs. ferrocenium/ferrocene couple). The presence of CO assists the formation of 1 after electrochemically induced loss of PPh3 during the voltammetric experiment of 2. Using DFT calculations we provide an explanation for the difference in stabilities between the Fe–PPh3 and Fe–P(OEt)3 bonds.
Type de document :
Article dans une revue
Dalton Transactions, Royal Society of Chemistry, 2015, 44 (16), pp.7177 - 7189. 〈http://pubs.rsc.org/en/content/articlelanding/2015/dt/c5dt00064e#!divAbstract〉. 〈10.1039/C5DT00064E〉
Domaine :
Liste complète des métadonnées

http://hal.univ-brest.fr/hal-01538592
Contributeur : Nicolas Renard <>
Soumis le : mardi 13 juin 2017 - 17:06:01
Dernière modification le : jeudi 11 janvier 2018 - 06:17:06

Identifiants

Collections

Citation

Laith R. Almazahreh, Wolfgang Imhof, Jean Talarmin, Philippe Schollhammer, Helmar Gorls, et al.. Ligand effects on the electrochemical behavior of [Fe2(CO)5(L){μ-(SCH2)2(Ph)P[double bond, length as m-dash]O}] (L = PPh3, P(OEt)3) hydrogenase model complexes . Dalton Transactions, Royal Society of Chemistry, 2015, 44 (16), pp.7177 - 7189. 〈http://pubs.rsc.org/en/content/articlelanding/2015/dt/c5dt00064e#!divAbstract〉. 〈10.1039/C5DT00064E〉. 〈hal-01538592〉

Partager

Métriques

Consultations de la notice

57