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Enantioselective Nazarov Cyclization Catalyzed by a Cinchona Alkaloid Derivative.

ABSTRACT: Nucleophilic catalysts for a 1,6 addition/Nazarov cyclization/elimination sequence were evaluated for their ability to induce enantioselectivity in the electrocyclization step. Of the tertiary amines examined, it was found that a cinchona alkaloid derivative was able to generate substituted 5-hydroxy ?-methylene cyclopentenones with excellent enantioselectivity. The study results suggest that successful cyclization depends upon the ability of the dienyl diketone substrate to readily adopt an s-cis conformation.

SUBMITTER: Huang YW

PROVIDER: S-EPMC4465120 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Enantioselective Nazarov Cyclization Catalyzed by a Cinchona Alkaloid Derivative.

Huang Yu-Wen YW Frontier Alison J AJ

Tetrahedron letters 20150601 23

Nucleophilic catalysts for a 1,6 addition/Nazarov cyclization/elimination sequence were evaluated for their ability to induce enantioselectivity in the electrocyclization step. Of the tertiary amines examined, it was found that a cinchona alkaloid derivative was able to generate substituted 5-hydroxy γ-methylene cyclopentenones with excellent enantioselectivity. The study results suggest that successful cyclization depends upon the ability of the dienyl diketone substrate to readily adopt an <i> ...[more]

PMID: 26085696

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