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Selective Hydrogen Atom Abstraction through Induced Bond Polarization: Direct ?-Arylation of Alcohols through Photoredox, HAT, and Nickel Catalysis.

ABSTRACT: The combination of nickel metallaphotoredox catalysis, hydrogen atom transfer catalysis, and a Lewis acid activation mode, has led to the development of an arylation method for the selective functionalization of alcohol ?-hydroxy C-H bonds. This approach employs zinc-mediated alcohol deprotonation to activate ?-hydroxy C-H bonds while simultaneously suppressing C-O bond formation by inhibiting the formation of nickel alkoxide species. The use of Zn-based Lewis acids also deactivates other hydridic bonds such as ?-amino and ?-oxy C-H bonds. This approach facilitates rapid access to benzylic alcohols, an important motif in drug discovery. A 3-step synthesis of the drug Prozac exemplifies the utility of this new method.

SUBMITTER: Twilton J

PROVIDER: S-EPMC6448405 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Selective Hydrogen Atom Abstraction through Induced Bond Polarization: Direct α-Arylation of Alcohols through Photoredox, HAT, and Nickel Catalysis.

Twilton Jack J Christensen Melodie M DiRocco Daniel A DA Ruck Rebecca T RT Davies Ian W IW MacMillan David W C DWC

Angewandte Chemie (International ed. in English) 20180406 19

The combination of nickel metallaphotoredox catalysis, hydrogen atom transfer catalysis, and a Lewis acid activation mode, has led to the development of an arylation method for the selective functionalization of alcohol α-hydroxy C-H bonds. This approach employs zinc-mediated alcohol deprotonation to activate α-hydroxy C-H bonds while simultaneously suppressing C-O bond formation by inhibiting the formation of nickel alkoxide species. The use of Zn-based Lewis acids also deactivates other hydrid ...[more]

PMID: 29490112

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