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Title: Distinct Bimetallic Cooperativity Among Water Reduction Catalysts Containing [Co III Co III ], [Ni II Ni II ], and [Zn II Zn II ] Cores

Three binuclear species [LCoIII2(μ‐Pz)2](ClO4)3(1), [LNiII2(CH3OH)2Cl2]ClO4(2), and [LZnII2Cl2]PF6(3) supported by the deprotonated form of the ligand 2,6‐bis[bis(2‐pyridylmethyl) amino‐methyl]‐4‐methylphenol were synthesized, structurally characterized as solids and in solution, and had their electrochemical and spectroscopic behavior established. Species13had their water reduction ability studied aiming to interrogate the possible cooperative catalytic activity between two neighboring metal centers. Species1and2reduced H2O to H2effectively at an applied potential of −1.6 VAg/AgCl, yielding turnover numbers of 2,820 and 2,290, respectively, after 30 minutes. Species3lacked activity and was used as a negative control to eliminate the possibility of ligand‐based catalysis. Pre‐ and post‐catalytic data gave evidence of the molecular nature of the process within the timeframe of the experiments. Species1showed structural, rather than electronic cooperativity, while species2displayed no obvious cooperativity. DFT methods complemented the experimental results determining plausible mechanisms.

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Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Chemistry – A European Journal
Medium: X
Sponsoring Org:
National Science Foundation
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