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Abstract The first cobalt‐catalyzed cross‐coupling of aryl tosylates with alkyl and aryl Grignard reagents is reported. The catalytic system uses CoF3and NHCs (NHC=N‐heterocyclic carbene) as ancillary ligands. The reaction proceeds via highly selective C−O bond functionalization, leading to the corresponding products in up to 98 % yield. The employment of alkyl Grignard reagents allows to achieve a rare C(sp2)−C(sp3) cross‐coupling of C−O electrophiles, circumventing isomerization and β‐hydride elimination problems. The use of aryl Grignards leads to the formation of biaryls. The C−O cross‐coupling sets the stage for a sequential cross‐coupling by exploiting the orthogonal selectivity of the catalytic system.
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Nickel(IV) Intermediates in Aminoquinoline-Directed C(sp 2 )–C(sp 3 ) Coupling
- Award ID(s):
- 1954985
- PAR ID:
- 10440657
- Date Published:
- Journal Name:
- Journal of the American Chemical Society
- Volume:
- 144
- Issue:
- 46
- ISSN:
- 0002-7863
- Page Range / eLocation ID:
- 21030 to 21034
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/jacs.2c10778
