Abstract
A nickel(II) bis(diphosphine) complex, [Ni(P Me 2N Ph 2) 2](BF 4) 2 (P Me 2N Ph 2 = 1,5-diphenyl-3,7-dimethyl- 1,5-diaza-3,7-diphosphacyclooctane), has been synthesized and characterized. This complex, which contains pendant amines in the diphosphine ligand, is an electrocatalyst for hydrogen production by proton reduction. Using [(DMF)H]OTf as the acid, a turnover frequency of 1,540 s -1 was obtained with no added water, and a turnover frequency of 6,700 s -1 was found with 1.0 M water added. Thermochemical studies show that the hydride donor ability of [HNi(P Me 2N Ph 2) 2](BF 4) is δG° H- = 54.0 kcal/mol, and we estimate a driving force for H 2 elimination of 13.8 kcal/mol. [Ni(P Me 2N Ph 2) 2](BF 4) 2 is the fastest H 2 production catalyst in the [Ni(P R 2N R' 2) 2] (BF 4) 2 family of complexes.
Original language | English |
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Pages (from-to) | 720-727 |
Number of pages | 8 |
Journal | ACS Catalysis |
Volume | 2 |
Issue number | 5 |
DOIs | |
Publication status | Published - May 4 2012 |
Keywords
- electrocatalysis
- hydrogen
- nickel
- pendant amine
- proton reduction
- proton relay
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)