Rationalizing Photo‐Triggered Hydrogen Evolution Using Polypyridine Cobalt Complexes: Substituent Effects on Hexadentate Chelating Ligands
نویسندگان
چکیده
Four novel polypyridine cobalt(II) complexes were developed based on a hexadentate ligand scaffold bearing either electron-withdrawing (−CF3) or electron-donating (−OCH3) groups in different positions of the ligand. Experiments and theoretical calculations combined to perform systematic investigation effect modification hydrogen evolution reaction. The results indicated that position, rather than type substituent, was dominating factor promoting catalysis. best performances observed upon introduction substituents pyridine moiety ligand, which promoted formation Co(II)H intermediate via intramolecular proton transfer reactions with low activation energy. Quantum yields 11.3 10.1 %, maximum turnover frequencies 86.1 76.6 min−1, numbers 5520 4043 obtained, respectively, −OCH3 −CF3 substituent.
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ژورنال
عنوان ژورنال: Chemsuschem
سال: 2021
ISSN: ['1864-5631', '1864-564X']
DOI: https://doi.org/10.1002/cssc.202100161