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Direct Catalytic Asymmetric Doubly Vinylogous Michael Addition of ?,?-Unsaturated ?-Butyrolactams to Dienones.

ABSTRACT: An asymmetric doubly vinylogous Michael addition (DVMA) of ?,?-unsaturated ?-butyrolactams to sterically congested ?-substituted cyclic dienones with high site-, diastereo-, and enantioselectivity has been achieved. An unprecedented DVMA/vinylogous Michael addition/isomerization cascade reaction affords chiral fused tricyclic ?-lactams with four newly formed stereocenters.

SUBMITTER: Gu X

PROVIDER: S-EPMC4678421 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Direct Catalytic Asymmetric Doubly Vinylogous Michael Addition of α,β-Unsaturated γ-Butyrolactams to Dienones.

Gu Xiaodong X Guo Tingting T Dai Yuanyuan Y Franchino Allegra A Fei Jie J Zou Chuncheng C Dixon Darren J DJ Ye Jinxing J

Angewandte Chemie (International ed. in English) 20150715 35

An asymmetric doubly vinylogous Michael addition (DVMA) of α,β-unsaturated γ-butyrolactams to sterically congested β-substituted cyclic dienones with high site-, diastereo-, and enantioselectivity has been achieved. An unprecedented DVMA/vinylogous Michael addition/isomerization cascade reaction affords chiral fused tricyclic γ-lactams with four newly formed stereocenters. ...[more]

PMID: 26184079

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