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This content will become publicly available on August 29, 2026

Title: Mechanism of Phenol Oxidation by CuCl 2
Although copper‐catalyzed organic transformations are prevalent, insights into the interactions of phenols with simple copper(II) salts are not well understood. In contrast, inspired by the oxygenase‐type modifications of the phenolic substrates, the reactions of substituted phenols with metastable copper–oxygen intermediates are well documented. The present report sheds light on the reactions of substituted phenols with benchtop stable CuCl2salt and the role of a common base like triethylamine. Moreover, the reactions of substituted phenols with CuCl2in the presence of weakly coordinating tripodalN‐nitrosated ligandL3NOhave been illustrated, while a closely related tripodal copper(II) complexL3HCuCl2(2) of the corresponding non‐nitrosated ligandL3Hdoes not react with the phenolic substrates. Phenol reactions with CuCl2in the presence of theL3NOligand enable in depth mechanistic investigation, thereby illustrating a bimolecular rate law with ΔH‡= 15.13 kcal mol−1, ΔS‡ = −9.6 eu, and kinetic isotope effectk2(ArOH)/k2(ArOD) in the range of 1.35–1.43. Thus, these findings suggest that simple copper(II) salts like CuCl2are capable of facilitating a proton‐coupled electron transfer (PCET) pathway.  more » « less
Award ID(s):
1847926
PAR ID:
10654101
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
European Journal of Inorganic Chemistry
Date Published:
Journal Name:
European Journal of Inorganic Chemistry
Volume:
28
Issue:
24
ISSN:
1434-1948
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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