| Autor: |
Kariyawasam Pathirana KD; Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States., Ghosh P; Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States., Hsieh CH; Department of Chemistry, Tamkang University, New Taipei City, Taiwan., Elrod LC; Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States., Bhuvanesh N; Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States., Darensbourg DJ; Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States., Darensbourg MY; Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States. |
| Jazyk: |
angličtina |
| Zdroj: |
Inorganic chemistry [Inorg Chem] 2020 Mar 16; Vol. 59 (6), pp. 3753-3763. Date of Electronic Publication: 2020 Feb 21. |
| DOI: |
10.1021/acs.inorgchem.9b03409 |
| Abstrakt: |
The development of ligands with specific stereo- and electrochemical requirements that are necessary for catalyst design challenges synthetic chemists in academia and industry. The crucial aza-dithiolate linker in the active site of [FeFe]-H 2 ase has inspired the development of synthetic analogues that utilize ligands which serve as conventional σ donors with pendant base features for H + binding and delivery. Several MN 2 S 2 complexes (M = Ni 2+ , [Fe(NO)] 2+ , [Co(NO)] 2+ , etc.) utilize these cis-dithiolates to bind low valent metals and also demonstrate the useful property of hemilability, i.e., alternate between bi- and monodentate ligation. Herein, synthetic efforts have led to the isolation and characterization of three heterotrimetallics that employ metallodithiolato ligand binding to di-iron scaffolds in three redox levels, (μ-pdt)[Fe(CO) 3 ] 2 , (μ-pdt)[Fe(CO) 3 ][(Fe(NO)) II (IMe)(CO)] + , and (μ-pdt)(μ-H)[Fe II (CO) 2 (PMe 3 )] 2 + to generate (μ-pdt)[(Fe I (CO) 3 ][Fe I (CO) 2 ·NiN 2 S 2 ] ( 1 ), (μ-pdt)[Fe I (CO) 3 ][(Fe(NO)) II (IMe)(CO)] + ( 2 ), and (μ-pdt)(μ-H)[Fe II (CO) 2 (PMe 3 )][Fe II (CO)(PMe 3 )·NiN 2 S 2 ] + ( 3 ) complexes (pdt = 1,3-propanedithiolate, IMe = 1,3-dimethylimidazole-2-ylidene, NiN 2 S 2 = [N,N'-bis(2-mercaptidoethyl)-1,4-diazacycloheptane] nickel(II)). These complexes display efficient metallodithiolato binding to the di-iron scaffold with one thiolate-S, which allows the free unbound thiolate to potentially serve as a built-in pendant base to direct proton binding, promoting a possible Fe-H - ··· + H-S coupling mechanism for the electrocatalytic hydrogen evolution reaction (HER) in the presence of acids. Ligand substitution studies on 1 indicate an associative/dissociative type reaction mechanism for the replacement of the NiN 2 S 2 ligand, providing insight into the Fe-S bond strength. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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