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  • Enhanced activity of bulky N-heterocyclic carbenes in nickel–NHC catalyzed Kumada–Corriu cross-coupling of aryl tosylates
Title: Enhanced activity of bulky N-heterocyclic carbenes in nickel–NHC catalyzed Kumada–Corriu cross-coupling of aryl tosylates
Over the last decades, advances in Ni catalysis have expanded the chemical reactivity of cross-coupling reactions and led to the discovery of catalytic systems that are now widely applied in industrial and academic research. Herein, we report the cross-coupling of aryl tosylates by Ni–NHC catalysis using bulky N-heterocyclic carbene ligands. A notable feature of this operationally-simple method is the combination of ‘fluoride effect’ to minimize homocoupling and bulky NHC ligands, such as IPr* and IPr* MeO , that enhance the activity of Ni in cross-coupling and prevent hydrolysis of sensitive oxygen electrophiles. A broad range of aryl and heteroaryl tosylates underwent cross-coupling with high efficiency. The finding that easily accessible, bulky NHCs with flexible CHPh 2 wingtips enhance the reactivity in Ni–NHC cross-coupling represents a powerful approach for catalysis.  more » « less
Award ID(s):
1650766
PAR ID:
10412448
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
12
Issue:
24
ISSN:
2044-4753
Page Range / eLocation ID:
7275 to 7280
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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