Premium
Redox Communication within Multinuclear Iron–Sulfur Complexes Related to Electronic Interplay in the Active Site of [FeFe]Hydrogenase
Author(s) -
Chu KaiTi,
Liu YuChiao,
Huang YiLan,
Lee GeneHsiang,
Tseng MeiChun,
Chiang MingHsi
Publication year - 2015
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201406101
Subject(s) - chemistry , steric effects , unpaired electron , stacking , redox , photochemistry , electronic effect , sulfur , metal , electronic structure , active site , crystallography , stereochemistry , radical , inorganic chemistry , catalysis , computational chemistry , organic chemistry
The one‐electron oxidations of a Fe 2 complex lead to the formation of a persistent metal‐stabilized thiyl radical Fe 2 species, mixed‐valent Fe 4 , and Fe 8 complexes. The unpaired spin in the Fe 2 radical species delocalizes over the Fe 2 and the aromatic dithiolate, mostly on the terminal sulfur. The subsequent dimerization of the singly oxidized Fe 2 to the Fe 4 retains the partial thiyl radical character. For an analogue with less steric hindrance, the π–π stacking interaction between the dithiolato aromatic rings induces generation of the Fe 8 , in which process electronic structures of the species are modulated through reducing the thiyl radical to the thiolate. Electronic reorganization repeats when the Fe 8 is converted to Fe 4 . Electronic interplay in the complexes decreases the energy gap of frontier MOs and buffers electronic impacts upon redox events. Easier accessible redox potentials and increased stability of the species are facilitated. The results demonstrate that electronic versatility of the benzenedithiolate exerts pronounced influences on electronic and coordination structure of the metal complexes.