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Title: Revised Mechanism of C(sp 3 )–C(sp 3 ) Reductive Elimination from Ni(II) with the Assistance of a Z-Type Metalloligand
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Author(s) / Creator(s):
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Date Published:
Journal Name:
Journal of the American Chemical Society
Page Range / eLocation ID:
2207 to 2218
Medium: X
Sponsoring Org:
National Science Foundation
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  1. 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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