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Nitro-enabled catalytic enantioselective formal umpolung alkenylation of ?-ketoesters.

ABSTRACT: A formal umpolung strategy is presented for the enantioselective installation of an alkenyl group with a terminal double bond at a tertiary center. This one-pot two-step sequence relies on the unique features of the nitro group, which after inverting the polarity of the alkenylating agent toward the desired bond formation, itself serves as a leaving group. The application of this protocol to cyclic ?-ketoesters results in densely functionalized products, bearing an all-carbon quaternary stereocenter including an alkenyl substituent with a terminal double bond, in high yields with excellent enantioselectivities.

SUBMITTER: Choudhury AR

PROVIDER: S-EPMC5625255 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Nitro-enabled catalytic enantioselective formal <i>umpolung</i> alkenylation of β-ketoesters.

Choudhury Abhijnan Ray AR Manna Madhu Sudan MS Mukherjee Santanu S

Chemical science 20170802 9

A formal <i>umpolung</i> strategy is presented for the enantioselective installation of an alkenyl group with a terminal double bond at a tertiary center. This one-pot two-step sequence relies on the unique features of the nitro group, which after inverting the polarity of the alkenylating agent toward the desired bond formation, itself serves as a leaving group. The application of this protocol to cyclic β-ketoesters results in densely functionalized products, bearing an all-carbon quaternary s ...[more]

PMID: 28989696

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