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Stereoselective synthesis of isoquinuclidines through an aza-[4 + 2] cycloaddition of chiral cyclic 2-amidodienes.

ABSTRACT: A highly stereoselective aza-[4 + 2] cycloaddition of chiral cyclic 2-amidodienes with N-sulfonyl aldimines is described. While this Lewis acid promoted heterocycloaddition provides an efficient strategy for constructing optically enriched isoquinuclidines, it is mechanistically intriguing. The cycloaddition favored the endo-II pathway in the absence of a viable bidentate coordination. This represents an unexpected switch from the anticipated endo-I selectivity obtained in the all-carbon cycloaddition.

SUBMITTER: Fang LC

PROVIDER: S-EPMC3969095 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of isoquinuclidines through an aza-[4 + 2] cycloaddition of chiral cyclic 2-amidodienes.

Fang Li-Chao LC Hsung Richard P RP

Organic letters 20140312 6

A highly stereoselective aza-[4 + 2] cycloaddition of chiral cyclic 2-amidodienes with N-sulfonyl aldimines is described. While this Lewis acid promoted heterocycloaddition provides an efficient strategy for constructing optically enriched isoquinuclidines, it is mechanistically intriguing. The cycloaddition favored the endo-II pathway in the absence of a viable bidentate coordination. This represents an unexpected switch from the anticipated endo-I selectivity obtained in the all-carbon cycload ...[more]

PMID: 24621094

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