Synthesis of Diiron Hydrogenase Mimics Bearing Hydroquinone and Related Ligands. Electrochemical and Computational Studies of the Mechanism of Hydrogen Production and the Role of O-H S Hydrogen Bonding
Document Type
Article
Publication Date
11-8-2010
Department
Physical & Earth Sciences
Abstract
A new synthetic method for annulating hydroquinones to Fe2S 2(CO)6 moieties is reported. Piperidine catalyzed a multistep reaction between Fe2(μ-SH)2(CO)6 and quinones to afford bridged adducts in 26-76% yields. The hydroquinone adducts undergo reversible two-electron reductions. In the presence of acetic acid, hydrogen is produced catalytically with these adducts at potentials more negative than that of the initial reversible reduction. Spectroscopic studies suggest the presence of intramolecular hydrogen bonding between the phenolic OH groups and the adjacent sulfur atoms. Computations, which are in good agreement with the electrochemical studies and spectroscopic data, indicate that the hydrogen bonding is most important in the reduced forms of the catalysts. This hydrogen bonding lowers the reduction potential for catalysis but also lowers the basicity and thereby the reactivity of the catalysts. © 2010 American Chemical Society.
DOI
10.1021/om100396j
First Page
5330
Last Page
5340
Volume
29
Issue
21
Publication Title
Organometallics
ISSN
0276-7333
Recommended Citation
Chen, Jinzhu; Vannucci, Aaron K.; Mebi, Charles A.; Okumura, Noriko; Borowski, Susan C.; Swenson, Matthew; Lockett, L. Tori; Evans, Dennis H.; Glass, Richard S.; and Lichtenberger, Dennis L., "Synthesis of Diiron Hydrogenase Mimics Bearing Hydroquinone and Related Ligands. Electrochemical and Computational Studies of the Mechanism of Hydrogen Production and the Role of O-H S Hydrogen Bonding" (2010). Faculty Publications - Physical & Earth Sciences. 9.
https://orc.library.atu.edu/faculty_pub_phys/9