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Catalytic, asymmetric indolizidinone aza-quaternary stereocenter synthesis: expedient synthesis of the cylindricine alkaloid core.

ABSTRACT: The Rh(I)•CKphos catalyzed [2 + 2 + 2] cycloaddition of 1,1-disubstituted alkenyl isocyanates and alkyl alkynes selectively forms previously inaccessible vinylogous amide indolizidinone cycloadducts, establishing an aza-quaternery stereocenter with excellent enantioselectivities (up to 98% ee). This advance enables a seven step catalytic, asymmetric synthesis of the tricyclic core of the cylindricine alkaloids with excellent control of product selectivity as well as regio- and enantioselectivity.

SUBMITTER: Dalton DM

PROVIDER: S-EPMC3809156 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Catalytic, asymmetric indolizidinone aza-quaternary stereocenter synthesis: expedient synthesis of the cylindricine alkaloid core.

Dalton Derek M DM Rovis Tomislav T

Organic letters 20130430 10

The Rh(I)•CKphos catalyzed [2 + 2 + 2] cycloaddition of 1,1-disubstituted alkenyl isocyanates and alkyl alkynes selectively forms previously inaccessible vinylogous amide indolizidinone cycloadducts, establishing an aza-quaternery stereocenter with excellent enantioselectivities (up to 98% ee). This advance enables a seven step catalytic, asymmetric synthesis of the tricyclic core of the cylindricine alkaloids with excellent control of product selectivity as well as regio- and enantioselectivity ...[more]

PMID: 23631448

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