Diiron models for the active site of Fe-only hydrogenase with terminal organosulfur ligation: Synthesis, structures and electrochemistry

摘要

Diiron model complexes (mu-SCH2CH2CH2S)Fe-2(CO)(5)L with thioether-substitution, L = S(CH2CH3)(2) (2), S(CH2CH3)(CH2CH2Cl) (3), S(CH2CH3)(C6H5) (4), or sulfoxide-substitution, L = SO(CH2CH2CH3)(2) (5), SO(CH3)(2) (6), were synthesized as active site analogues of Fe-only hydrogenase. The organosulfur ligands were introduced into the diiron centers via moderately stable intermediates following two routes. The X-ray crystallographic structures of complexes 2-6 show the apical positions of terminal organosulfur ligands. The electrochemical behaviors of the model complexes were investigated, especially for the interesting properties of the derivative of 6 which is proposed to be the first model with weak donor ligand similar to CO. (C) 2007 Elsevier Inc. All rights reserved.