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  • Controlling the optical and catalytic properties of artificial metalloenzyme photocatalysts using chemogenetic engineering
Title: Controlling the optical and catalytic properties of artificial metalloenzyme photocatalysts using chemogenetic engineering
Visible light photocatalysis enables a broad range of organic transformations that proceed via single electron or energy transfer. Metal polypyridyl complexes are among the most commonly employed visible light photocatalysts. The photophysical properties of these complexes have been extensively studied and can be tuned by modifying the substituents on the pyridine ligands. On the other hand, ligand modifications that enable substrate binding to control reaction selectivity remain rare. Given the exquisite control that enzymes exert over electron and energy transfer processes in nature, we envisioned that artificial metalloenzymes (ArMs) created by incorporating Ru( ii ) polypyridyl complexes into a suitable protein scaffold could provide a means to control photocatalyst properties. This study describes approaches to create covalent and non-covalent ArMs from a variety of Ru( ii ) polypyridyl cofactors and a prolyl oligopeptidase scaffold. A panel of ArMs with enhanced photophysical properties were engineered, and the nature of the scaffold/cofactor interactions in these systems was investigated. These ArMs provided higher yields and rates than Ru(Bpy) 3 2+ for the reductive cyclization of dienones and the [2 + 2] photocycloaddition between C -cinnamoyl imidazole and 4-methoxystyrene, suggesting that protein scaffolds could provide a means to improve the efficiency of visible light photocatalysts.  more » « less
Award ID(s):
1920026
PAR ID:
10368176
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
13
Issue:
5
ISSN:
2041-6520
Page Range / eLocation ID:
1459 to 1468
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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