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Diastereoselective Synthesis of Spirocyclopropanes under Mild Conditions via Formal [2 + 1] Cycloadditions Using 2,3-Dioxo-4-benzylidene-pyrrolidines.

ABSTRACT: A highly diastereoselective cyclopropanation of cyclic enones with sulfur ylides was developed under catalyst-free conditions, producing multifunctional spirocyclopropanes in generally excellent yields (up to 99% yield and >99:1 d.r.). The asymmetric version of this method was realized by using an easily available chiral sulfur ylide, affording products with moderate to good stereoselectivity.

SUBMITTER: Li Y

PROVIDER: S-EPMC6155796 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Diastereoselective Synthesis of Spirocyclopropanes under Mild Conditions via Formal [2 + 1] Cycloadditions Using 2,3-Dioxo-4-benzylidene-pyrrolidines.

Li Yi Y Li Qing-Zhu QZ Huang Li L Liang Hong H Yang Kai-Chuan KC Leng Hai-Jun HJ Liu Yue Y Shen Xu-Dong XD Gou Xiao-Jun XJ Li Jun-Long JL

Molecules (Basel, Switzerland) 20170222 2

A highly diastereoselective cyclopropanation of cyclic enones with sulfur ylides was developed under catalyst-free conditions, producing multifunctional spirocyclopropanes in generally excellent yields (up to 99% yield and >99:1 d.r.). The asymmetric version of this method was realized by using an easily available chiral sulfur ylide, affording products with moderate to good stereoselectivity. ...[more]

PMID: 28241452

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