Solvent‐ and Halide‐Induced (Inter)conversion between Iron(II)‐Disulfide and Iron(III)‐Thiolate Complexes. Issue 46 (29th June 2018)

• Record Type: Journal Article
• Authors: Wang, Lianke; Cantú Reinhard, Fabián G.; Philouze, Christian; Demeshko, Serhiy; de Visser, Sam P.; Meyer, Franc; Gennari, Marcello; Duboc, Carole
• Is Part Of: Chemistry. Volume 24:Issue 46(2018)
• Page Start: 11973
• Page End: 11982
• Publication Date: 2018-06-29
• Subjects: iron complexes -- metal-thiolate -- molecular switches -- redox chemistry -- thiolate-disulfide interconversion; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201801377
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Disulfide/thiolate interconversion controlled by Cu is proposed to be involved in relevant biological processes. In analogy to Cu, it can be envisaged that Fe also participates in the control of similar biological processes. We describe here Fe complexes that undergo Fe III ‐thiolate/Fe II ‐disulfide (inter)conversion mediated by halide (de)coordination, and by the nature of the solvent. The dinuclear Fe II ‐disulfide complex [Fe II 2 (LSSL)] 2+ ((LS) 2− =2, 2′‐(2, 2′‐bipyridine‐6, 6′‐diyl)bis(1, 1‐diphenylethanethiolate), (LSSL) 2− =the corresponding disulfide ligand) shows solvent‐dependent properties. Whereas in a non‐coordinating solvent (CH2 Cl2 ) the dinuclear Fe II ‐disulfide complex is the only stable form, in the presence of coordinating solvents like MeCN or DMF it is partly or fully converted into mononuclear Fe III ‐thiolate species having a bound solvent molecule ([Fe III (LS)(Solv)] +, Solv=DMF, MeCN). Addition of Cl − to a CH2 Cl2 solution containing the Fe II ‐disulfide dinuclear complex leads to the fast and quantitative formation of a mononuclear Fe III ‐thiolate species with a bound Cl −, that is, ([Fe III (LS)Cl]). The reverse reaction can be achieved by addition of Li[[B(C6 F5 )4 ]. In relation to the metal–sulfur electronic distribution, the comparison between the redox properties of the Fe, Mn and Co complexes involved in these M III ‐thiolate/M II ‐disulfide interconversion processes allow one to rationalize their respective efficiency. Abstract : With a little help from Fe : The first disulphide/thiolate molecular switch based on iron is reported and compared to the parent cobalt‐ and manganese‐based systems.