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Diastereodivergent organocatalysis for the asymmetric synthesis of chiral annulated furans.

ABSTRACT: Disclosed herein is a stereoselective method for the synthesis of 2,3-furan fused carbocycles bearing adjacent quaternary and tertiary carbon stereocenters. The chemistry is based on an asymmetric addition of ?-ketoesters to 2-(1-alkynyl)-2-alkene-1-ones catalysed by natural cinchona alkaloids followed by a silver-catalysed intramolecular cycloisomerisation. By exploiting the distinct catalysis modes of quinine, which can act either as a general base or, upon opportune modifications, as a phase transfer catalyst, a complete switch of the enforced sense of diastereoinduction is achieved. The stereodivergent systems enable access to the full matrix of all possible stereoisomeric products.

SUBMITTER: Verrier C

PROVIDER: S-EPMC5707493 | biostudies-other | 2015 Jul

REPOSITORIES: biostudies-other

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Diastereodivergent organocatalysis for the asymmetric synthesis of chiral annulated furans.

Verrier Charlie C Melchiorre Paolo P

Chemical science 20150427 7

Disclosed herein is a stereoselective method for the synthesis of 2,3-furan fused carbocycles bearing adjacent quaternary and tertiary carbon stereocenters. The chemistry is based on an asymmetric addition of β-ketoesters to 2-(1-alkynyl)-2-alkene-1-ones catalysed by natural cinchona alkaloids followed by a silver-catalysed intramolecular cycloisomerisation. By exploiting the distinct catalysis modes of quinine, which can act either as a general base or, upon opportune modifications, as a phase ...[more]

PMID: 29218190

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