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Nickel-Catalyzed Cross-Coupling of Vinyl Dioxanones to Form Enantiomerically Enriched Cyclopropanes.

ABSTRACT: Under the conditions of nickel(0) catalysis, enantiomerically enriched vinyl dioxanones engage boroxines or B2(pin)2 in stereospecific cross-coupling to form diverse tetrasubstituted cyclopropanes bearing all-carbon quaternary stereocenters. The collective data corroborate a mechanism involving nickel(0)-mediated benzylic oxidative addition with inversion of stereochemistry followed by reversible olefin insertion to form a (cyclopropylcarbinyl)nickel complex, which upon reductive elimination releases the cyclopropane.

SUBMITTER: Guo YA

PROVIDER: S-EPMC5651680 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Nickel-Catalyzed Cross-Coupling of Vinyl Dioxanones to Form Enantiomerically Enriched Cyclopropanes.

Guo Yi-An YA Liang Tao T Kim Seung Wook SW Xiao Hongde H Krische Michael J MJ

Journal of the American Chemical Society 20170510 20

Under the conditions of nickel(0) catalysis, enantiomerically enriched vinyl dioxanones engage boroxines or B<sub>2</sub>(pin)<sub>2</sub> in stereospecific cross-coupling to form diverse tetrasubstituted cyclopropanes bearing all-carbon quaternary stereocenters. The collective data corroborate a mechanism involving nickel(0)-mediated benzylic oxidative addition with inversion of stereochemistry followed by reversible olefin insertion to form a (cyclopropylcarbinyl)nickel complex, which upon red ...[more]

PMID: 28489371

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