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Nickel(ii)-catalyzed enantioselective cyclopropanation of 3-alkenyl-oxindoles with phenyliodonium ylide via free carbene.

ABSTRACT: A chiral Lewis acid-promoted enantioselective cyclopropanation using phenyliodonium ylide as the carbene precursor was developed. A variety of spirocyclopropane-oxindoles with contiguous tertiary and all carbon quaternary centers were obtained in excellent outcomes (up to 99% yield, >19?:?1 d.r., up to 99% ee). EPR spectroscopy study supported a stepwise biradical mechanism.

SUBMITTER: Guo J

PROVIDER: S-EPMC5477038 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Nickel(ii)-catalyzed enantioselective cyclopropanation of 3-alkenyl-oxindoles with phenyliodonium ylide <i>via</i> free carbene.

Guo Jing J Liu Yangbin Y Li Xiangqiang X Liu Xiaohua X Lin Lili L Feng Xiaoming X

Chemical science 20160104 4

A chiral Lewis acid-promoted enantioselective cyclopropanation using phenyliodonium ylide as the carbene precursor was developed. A variety of spirocyclopropane-oxindoles with contiguous tertiary and all carbon quaternary centers were obtained in excellent outcomes (up to 99% yield, >19 : 1 d.r., up to 99% ee). EPR spectroscopy study supported a stepwise biradical mechanism. ...[more]

PMID: 28660046

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