In:
Science, American Association for the Advancement of Science (AAAS), Vol. 370, No. 6523 ( 2020-12-18), p. 1454-1460
Abstract:
Palladium(II)-catalyzed carbon-hydrogen (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 palladium (Pd) loading (e.g., 10 mole %) 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 an inactive species. Systematic tuning of the quinone cocatalyst 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 Pd catalyst.
Type of Medium:
Online Resource
ISSN:
0036-8075
,
1095-9203
DOI:
10.1126/science.abd1085
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2020
detail.hit.zdb_id:
128410-1
detail.hit.zdb_id:
2066996-3
detail.hit.zdb_id:
2060783-0
SSG:
11
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