Cu‐containing metalloenzymes are known to catalyze oxygen activation through cooperative catalysis. In the current work, we report the design of synthetic polymer Cu catalysts using pyrene‐labelled poly(2‐hydroxy‐3‐dipicolylamino) propyl methacrylate (Py‐PGMADPA) to coordinate multiple Cu sites along polymer chains. The catalysts feature a pyrene end group that can form supramolecular π‐π stacking with conductive carbon to allow efficient immobilization of catalysts to the graphite electrode. Cu‐containing Py‐PGMADPA was examined for electrocatalytic oxygen reduction. The hybrid catalyst showed an onset potential of 0.5 V (vs. RHE) at pH 7 and 0.79 V at pH 13. The kinetic study indicated that the catalyst had a 2e−reduction of oxygen mainly mediated by Cu+centers. We demonstrated the importance of cooperative catalysis among Cu sites which did not exist for other transition metal ions, like Mn2+, Fe2+, Co2+, and Ni2+. The confinement of polymer chains promotes the activity and stabilizes Cu catalysts even at an extremely low Cu loading. The rational design of bioinspired polymer catalysts offers an alternative way to prepare synthetic mimics of metalloenzymes.
Bioinspired mononuclear Mn complexes for O 2 activation and biologically relevant reactions
A general interest in harnessing the oxidizing power of dioxygen (O 2 ) continues to motivate research efforts on bioinspired and biomimetic complexes to better understand how metalloenzymes mediate these reactions. The ubiquity of Fe- and Cu-based enzymes attracts significant attention and has resulted in many noteworthy developments for abiotic systems interested in direct O 2 reduction and small molecule activation. However, despite the existence of Mn-based metalloenzymes with important O 2 -dependent activity, there has been comparatively less focus on the development of these analogues relative to Fe- and Cu-systems. In this Perspective , we summarize important contributions to the development of bioinspired mononuclear Mn complexes for O 2 activation and studies on their reactivity, emphasizing important design parameters in the primary and secondary coordination spheres and outlining mechanistic trends.
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- Award ID(s):
- 2102156
- NSF-PAR ID:
- 10317603
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 50
- Issue:
- 46
- ISSN:
- 1477-9226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1DT03178C
