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Title: Tailored quinones support high-turnover Pd catalysts for oxidative C–H arylation with O 2
Palladium(II)-catalyzed C–H oxidation reactions could streamline the synthesis of pharmaceuticals, agrochemicals, and other complex organic molecules. Existing methods, however, commonly exhibit poor catalyst performance with high Pd loading (e.g., 10 mol %) and a need for (super)stoichiometric quantities of undesirable oxidants, such as benzoquinone and silver(I) salts. The present study probes the mechanism of a representative Pd-catalyzed oxidative C–H arylation reaction and elucidates mechanistic features that undermine catalyst performance, including substrate-consuming side reactions and sequestration of the catalyst as inactive species. Systematic tuning of the quinone co-catalyst overcomes these deleterious features. Use of 2,5-di- tert -butyl- p -benzoquinone enables efficient use of molecular oxygen as the oxidant, high reaction yields, and >1900 turnovers by the palladium catalyst.  more » « less
Award ID(s):
1700982
PAR ID:
10232035
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Science
ISSN:
0036-8075
Page Range / eLocation ID:
eabd1085
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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