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  • Creating, Preserving, and Directing Carboxylate Radicals in Ni-Catalyzed C(sp 3 )–H Acyloxylation of Ethers, Ketones, and Alkanes with Diacyl Peroxides
Title: Creating, Preserving, and Directing Carboxylate Radicals in Ni-Catalyzed C(sp 3 )–H Acyloxylation of Ethers, Ketones, and Alkanes with Diacyl Peroxides
The reaction of Ni(II) acetate with diacyl peroxides produces high-valence Ni-species capable of catalytic oxidative acyloxylation of C(sp3)–H bonds in ethers, ketones, and alkanes. The desired esters were obtained in 20–82% yields. Computational analysis suggests that activation of the peroxide moiety produces a dynamically interconverting mixture of catalytic Ni-species in the formal Ni(III) state. Remarkably, in these species, coordination of the RCO2 group at Ni preserves radical character at the carboxylate moiety (i.e., carboxylate radical acts as an “L-ligand”), so the latter can induce fast C–H abstraction. The spirocyclopropyl moiety prevents premature radical decarboxylation via a combination of hybridization factors and stereoelectronic effects. A variety of viable C–H activation patterns were identified experimentally and computationally.  more » « less
Award ID(s):
2102579
NSF-PAR ID:
10408843
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Organometallics
ISSN:
0276-7333
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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