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Title: CO 2 Activation with Manganese Tricarbonyl Complexes by an H‐Atom Responsive Benzimidazole Ligand
Abstract

Herein, we report the synthesis and characterization of two manganese tricarbonyl complexes, MnI(HL)(CO)3Br (1 a‐Br) and MnI(MeL)(CO)3Br (1 b‐Br) (where HL=2‐(2’‐pyridyl)benzimidazole; MeL=1‐methyl‐2‐(2’‐pyridy)benzimidazole) and assayed their electrocatalytic properties for CO2reduction. A redox‐active pyridine benzimidazole ancillary ligand in complex1 a‐Brdisplayed unique hydrogen atom transfer ability to facilitate electrocatalytic CO2conversion at a markedly lower reduction potential than that observed for1 b‐Br. Notably, a one‐electron reduction of1 a‐Bryields a structurally characterized H‐bonded binuclear Mn(I) adduct (2 a’) rather than the typically observed Mn(0)‐Mn(0) dimer, suggesting a novel method for CO2activation. Combining advanced electrochemical, spectroscopic, and single crystal X‐ray diffraction techniques, we demonstrate the use of an H‐atom responsive ligand may reveal an alternative, low‐energy pathway for CO2activation by an earth‐abundant metal complex catalyst.

 
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NSF-PAR ID:
10463095
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Chemistry – A European Journal
ISSN:
0947-6539
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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