Efficient generation of hydrogen from renewable resources requires development of catalysts that avoid deep wells and high barriers. Information about the energy landscape for H2 production can be obtained by chemical characterization of catalytic intermediates, but few have been observed to date. We have isolated and characterized a key intermediate in 2e(-) + 2H(+) → H2 catalysis. This intermediate, obtained by treatment of Cp*Rh(bpy) (Cp*, η(5)-pentamethylcyclopentadienyl; bpy, κ(2)-2,2'-bipyridyl) with acid, is not a hydride species but rather, bears [η(4)-Cp*H] as a ligand. Delivery of a second proton to this species leads to evolution of H2 and reformation of η(5)-Cp* bound to rhodium(III). With suitable choices of acids and bases, the Cp*Rh(bpy) complex catalyzes facile and reversible interconversion of H(+) and H2.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4988566 | PMC |
| http://dx.doi.org/10.1073/pnas.1606018113 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Electron acceptors promote proton-hydride tautomerism in low valent rhenium β-diketiminates.
Chem Commun (Camb)
April 2020
Department of Chemistry, University of California, Berkeley, CA 94720, USA.
We report a series of β-diketiminate (BDI) complexes in which tautomeric rhenium(iii) hydride and rhenium(i) protio-BDI species readily interconvert between the solid and solution states. This phenomenon, which is only operative when an electron-accepting ligand is bound to rhenium, was investigated by a combination of experimental and computational methods.
View Article and Find Full Text PDFProton-hydride tautomerism in hydrogen evolution catalysis.
Proc Natl Acad Sci U S A
June 2016
Beckman Institute, California Institute of Technology, Pasadena, CA 91125; Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125; Department of Chemistry, University of Kansas, Lawrence, KS 66044
Efficient generation of hydrogen from renewable resources requires development of catalysts that avoid deep wells and high barriers. Information about the energy landscape for H2 production can be obtained by chemical characterization of catalytic intermediates, but few have been observed to date. We have isolated and characterized a key intermediate in 2e(-) + 2H(+) → H2 catalysis.
View Article and Find Full Text PDFA reversible proton relay process mediated by hydrogen-bonding interactions in [FeFe]hydrogenase modeling.
Chemistry
July 2015
Institute of Chemistry, Academia Sinica, Nankang, Taipei 115 (Taiwan).
A reversible and temperature-dependent proton-relay process is demonstrated for a Fe2 complex possessing a terminal thiolate in the presence of nitrogen-based acids. The terminal sulfur site (S(t) ) of the complex forms a hydrogen-bond interaction with N,N-dimethylanilinium acid at 183 K. The Fe2 core, instead, is protonated to generate a bridging hydride at 298 K.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!