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Title: Copper Catalyzed sp3 C-H a-Acetylation
α-substituted ketones are important chemical targets as synthetic intermediates as well as functionalities in in natural products and pharmaceuticals. We report the sp3 C-H α-acetylation of sp3 C-H substrates R-H with arylmethyl ketones ArC(O)Me to provide α-alkylated ketones ArC(O)CH2R at RT with tBuOOtBu as oxidant via copper(I) β-diketiminato catalysts. Proceeding via alkyl radicals R•, this method enables α-substitution with bulky substituents without competing elimination that occurs in more traditional alkylation reactions between enolates and alkyl electrophiles. DFT studies suggest the intermediacy of copper(II) enolates [CuII](CH2C(O)Ar) that capture alkyl radicals R• to give R-CH2C(O)Ar under competing dimerization of the copper(II) enolate to give the 1,4-diketone ArC(O)CH2CH2C(O)Ar.  more » « less
Award ID(s):
1665348
NSF-PAR ID:
10231948
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
ChemRxiv
ISSN:
2573-2293
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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