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Streamlined asymmetric ?-difunctionalization of ynones.

ABSTRACT: Ynones are a unique class of structural motifs that show remarkable chemical versatility. Chiral ynones, particularly those possessing an ?-stereogenic center, are highly attractive templates for structural diversification. So far, only very limited examples have been reported for asymmetric ?-functionalization of ynones. Asymmetric double ?-functionalization of ynones remains elusive. Here we describe a streamlined strategy for asymmetric ?-difunctionalization of ynones. We developed a gold-catalyzed multicomponent condensation reaction from a simple ynone, an amine, and an electrophilic alkynylating reagent to generate a 1,2-dialkynyl enamine, a key stable and isolable intermediate. This intermediate can undergo asymmetric fluorination catalyzed by a chiral phosphoric acid derivative. Chiral ynones with an ?-quaternary carbon and containing a fluorine and an alkyne can be synthesized in high yield and high ee. The synthetic utility of this method is demonstrated by the synthesis of enantioenriched tri(hetero)arylmethyl fluorides.

SUBMITTER: Peng S

PROVIDER: S-EPMC5785506 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Streamlined asymmetric α-difunctionalization of ynones.

Peng Siyu S Wang Zhaofeng Z Zhang Linxing L Zhang Xinhao X Huang Yong Y

Nature communications 20180125 1

Ynones are a unique class of structural motifs that show remarkable chemical versatility. Chiral ynones, particularly those possessing an α-stereogenic center, are highly attractive templates for structural diversification. So far, only very limited examples have been reported for asymmetric α-functionalization of ynones. Asymmetric double α-functionalization of ynones remains elusive. Here we describe a streamlined strategy for asymmetric α-difunctionalization of ynones. We developed a gold-cat ...[more]

PMID: 29371601

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