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N-Heterocyclic carbene-catalyzed oxidative [3 + 2] annulation of dioxindoles and enals: cross coupling of homoenolate and enolate.

ABSTRACT: The N-heterocyclic carbene-catalyzed oxidative [3 + 2] annulation of dioxindole and enals was developed, giving the corresponding spirocyclic oxindole-?-lactones in good yields with high to excellent diastereo- and enantioselectivities. The challenging aliphatic enals worked effectively using this strategy. The oxidative cross coupling of homoenolate and enolate via single electron transfer was proposed as the key step for the reaction.

SUBMITTER: Chen XY

PROVIDER: S-EPMC5384455 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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N-Heterocyclic carbene-catalyzed oxidative [3 + 2] annulation of dioxindoles and enals: cross coupling of homoenolate and enolate.

Chen Xiang-Yu XY Chen Kun-Quan KQ Sun De-Qun DQ Ye Song S

Chemical science 20161109 3

The N-heterocyclic carbene-catalyzed oxidative [3 + 2] annulation of dioxindole and enals was developed, giving the corresponding spirocyclic oxindole-γ-lactones in good yields with high to excellent diastereo- and enantioselectivities. The challenging aliphatic enals worked effectively using this strategy. The oxidative cross coupling of homoenolate and enolate via single electron transfer was proposed as the key step for the reaction. ...[more]

PMID: 28451308

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