Release Time:2019-03-10  Hits:

Indexed by: Journal Article

Date of Publication: 2008-05-14

Journal: DALTON TRANSACTIONS

Included Journals: SCIE、PubMed、EI

Volume: 18

Issue: 18

Page Number: 2400-2406

ISSN: 1477-9226

Abstract: Four diiron dithiolate complexes containing ortho- acylamino- functionalized arenethiolato ligands, [(mu-S-2-RCONHC(6)H(4))(2)Fe(2)(CO)(6)] (R=CH(3), 1; CF(3), 2; C(6)H(5), 3; 4-FC(6)H(4), 4), were synthesized and well characterized as biomimetic models of the Fe-Fe hydrogenase active site. The molecular structures of 3 and 4 were determined by X-ray crystallography. The intra-ligand NH center dot center dot center dot S hydrogen bonds were studied by the X-ray analysis and by the (1)H NMR spectroscopy. The contribution of the NH center dot center dot center dot S hydrogen bonds to the reduction potentials of complexes 1-4 was investigated by electrochemistry. The first reduction potentials of complexes 1-4 exhibit large positive shifts, that is, 220-320 mV in comparison to that of the analogous complex [(mu- SPh)(2)Fe(2)(CO)(6)] and 370-470 mV to that of [(mu- pdt)(2)Fe(2)(CO)(6)] (pdt = propane-1,3-dithiolato). Complex 4 is capable of electrocatalysing proton reduction of acetic acid at relatively low overpotential ( ca. 0.2 V) in acetonitrile.