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Cooperative NHC and Photoredox Catalysis for the Synthesis of ?-Trifluoromethylated Alkyl Aryl Ketones.

ABSTRACT: Despite the great potential of radical chemistry in organic synthesis, N-heterocyclic carbene (NHC)-catalyzed reactions involving radical intermediates are not well explored. This communication reports the three-component coupling of aroyl fluorides, styrenes and the Langlois reagent (CF₃ SO₂ Na) to give various ?-trifluoromethylated alkyl aryl ketones with good functional group tolerance in moderate to high yields by cooperative photoredox/NHC catalysis. The alkene acyltrifluoromethylation proceeds via radical/radical cross coupling of ketyl radicals with benzylic C-radicals. The ketyl radicals are generated via SET reduction of in situ formed acylazolium ions whereas the benzylic radicals derive from trifluoromethyl radical addition onto styrenes.

SUBMITTER: Meng QY

PROVIDER: S-EPMC7693039 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Cooperative NHC and Photoredox Catalysis for the Synthesis of β-Trifluoromethylated Alkyl Aryl Ketones.

Meng Qing-Yuan QY Döben Nadine N Studer Armido A

Angewandte Chemie (International ed. in English) 20200901 45

Despite the great potential of radical chemistry in organic synthesis, N-heterocyclic carbene (NHC)-catalyzed reactions involving radical intermediates are not well explored. This communication reports the three-component coupling of aroyl fluorides, styrenes and the Langlois reagent (CF3 SO2 Na) to give various β-trifluoromethylated alkyl aryl ketones with good functional group tolerance in moderate to high yields by cooperative photoredox/NHC catalysis. The alkene acyltri ...[more]

PMID: 32700458

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