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  • Ligand‐to‐Metal Charge Transfer of Ag(II) CF 2 X Carboxylates: Quantum Yield and Electrophotocatalytic Arene Fluoroalkylation Tuned by X
Title: Ligand‐to‐Metal Charge Transfer of Ag(II) CF 2 X Carboxylates: Quantum Yield and Electrophotocatalytic Arene Fluoroalkylation Tuned by X
Abstract Incorporation of CF2X groups beyond CF3into arene scaffolds is underdeveloped despite these groups’ utility as halogen‐bond donors and as precursors to bioisosteres. Herein, we report the synthesis, characterization, and comparative photochemistry of a suite of [Ag(II)(bpy)2O2CCF2X]+and Ag(II)(bpy)(O2CCF2X)2(bpy = 2,2´‐bipyridine, X = F, CF3, Cl, Br, H, CH3) carboxylate complexes. We find a dramatic effect of the X substituent on the efficiency of generating CF2X radicals by ligand‐to‐metal charge transfer (LMCT), with Ag(II) photoreduction rates varying by over an order of magnitude and quantum yields spanning over 20%. We provide insight into how electronic and structural perturbations of the Ag(II)–O2CCF2X core are manifested in the LMCT quantum efficiency. With this information in hand, Ag(II)‐mediated electrophotocatalytic CF2X functionalization is carried out on a range of (hetero)arenes. This work expands the nascent field of Ag(II)‐based photocatalysis by allowing for (hetero)aryl–CF2X functionalization directly from unactivated fluoroalkyl carboxylate precursors.  more » « less
Award ID(s):
2216066
PAR ID:
10659177
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Publishing
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
64
Issue:
37
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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