Electron-Rich Diferrous–Phosphane–Thiolates Relevant to Fe-only Hydrogenase: Is Cyanide “Nature's Trimethylphosphane”?
Article first published online: 12 OCT 2005
Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chemistry - A European Journal
Volume 12, Issue 1, pages 90–98, December 16, 2005
How to Cite
van der Vlugt, J. I., Rauchfuss, T. B. and Wilson, S. R. (2006), Electron-Rich Diferrous–Phosphane–Thiolates Relevant to Fe-only Hydrogenase: Is Cyanide “Nature's Trimethylphosphane”?. Chem. Eur. J., 12: 90–98. doi: 10.1002/chem.200500752
- Issue published online: 9 DEC 2005
- Article first published online: 12 OCT 2005
- Manuscript Received: 30 JUN 2005
The two-step one-pot oxidative decarbonylation of [Fe2(S2C2H4)(CO)4(PMe3)2] (1) with [FeCp2]PF6, followed by addition of phosphane ligands, led to a series of diferrous dithiolato carbonyls 2–6, containing three or four phosphane ligands. In situ measurements indicate efficient formation of 12+ as the initial intermediate of the oxidation of 1, even when a deficiency of the oxidant was employed. Subsequent addition of PR3 gave rise to [Fe2(S2C2H4)(μ-CO)(CO)3(PMe3)3]2+ (2) and [Fe2(S2C2H4)(μ-CO)(CO)2(PMe3)2(PR3)2]2+ (R=Me 3, OMe 4) as principal products. One terminal CO ligand in these complexes was readily substituted by MeCN, and [Fe2(S2C2H4)(μ-CO)(CO)2(PMe3)3(MeCN)]2+ (5) and [Fe2(S2C2H4)(μ-CO)(CO)(PMe3)4(MeCN)]2+ (6) were fully characterized. Relevant to the Hred state of the active site of Fe-only hydrogenases, the unsymmetrical derivatives 5 and 6 feature a semibridging CO ligand trans to a labile coordination site.