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Enantioselective Synthesis of Biaryl Atropisomers via the Addition of Thiophenols into Aryl-Naphthoquinones.

ABSTRACT: We report a cinchona alkaloid catalyzed addition of thiophenol into rapidly interconverting aryl-naphthoquinones, resulting in stable biaryl atropisomers upon reductive methylation. An array of thiophenols and naphthoquinone substrates were evaluated, and we observed selectivities up to 98.5:1.5 e.r. Control of the quinone redox properties allowed us to study the stereochemical stabilities of each oxidation state of the substrates. The resulting enantioenriched products can also be moved on via an SNAr-like reaction sequence to arrive at stable derivatives with excellent enantioretention.

SUBMITTER: Maddox SM

PROVIDER: S-EPMC6238969 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Enantioselective Synthesis of Biaryl Atropisomers via the Addition of Thiophenols into Aryl-Naphthoquinones.

Maddox Sean M SM Dawson Gregory A GA Rochester Nicholas C NC Ayonon Arianna B AB Moore Curtis E CE Rheingold Arnold L AL Gustafson Jeffrey L JL

ACS catalysis 20180508 6

We report a cinchona alkaloid catalyzed addition of thiophenol into rapidly interconverting aryl-naphthoquinones, resulting in stable biaryl atropisomers upon reductive methylation. An array of thiophenols and naphthoquinone substrates were evaluated, and we observed selectivities up to 98.5:1.5 e.r. Control of the quinone redox properties allowed us to study the stereochemical stabilities of each oxidation state of the substrates. The resulting enantioenriched products can also be moved on via ...[more]

PMID: 30455999

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