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Electronic effects in the pt-catalyzed cycloisomerization of propargylic esters: synthesis of 2,3-disubstituted indolizines as a mechanistic probe.

ABSTRACT: The initial 5-exo versus 6-endo cyclization of the acyl group onto the activated alkyne of propargylic esters has been found to be dependent on electronic effects of the acyl, alkyne, and propargylic carbon substituents. These electronic effects control the ratio of 2,3-disubstituted versus 1,3-disubstituted indolizine products formed when substrates bearing pyridines at the alkyne terminus are used.

SUBMITTER: Hardin AR

PROVIDER: S-EPMC3342703 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Electronic effects in the pt-catalyzed cycloisomerization of propargylic esters: synthesis of 2,3-disubstituted indolizines as a mechanistic probe.

Hardin Alison R AR Sarpong Richmond R

Organic letters 20070911 22

The initial 5-exo versus 6-endo cyclization of the acyl group onto the activated alkyne of propargylic esters has been found to be dependent on electronic effects of the acyl, alkyne, and propargylic carbon substituents. These electronic effects control the ratio of 2,3-disubstituted versus 1,3-disubstituted indolizine products formed when substrates bearing pyridines at the alkyne terminus are used. ...[more]

PMID: 17845052

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