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Benzyltriboronates: Building Blocks for Diastereoselective Carbon-Carbon Bond Formation.

ABSTRACT: A highly diastereoselective carbon-carbon bond-forming reaction involving the tandem coupling of benzyltriboronates, enoates, and alkyl halides is described. This method was enabled by the discovery of ?-diimine nickel catalysts that promote the chemoselective triborylation of benzylic C(sp3)-H bonds using B2Pin2 (Pin = pinacolate). The C-H functionalization method is effective with methylarenes and for the diborylation of secondary benzylic C-H bonds, providing direct access to polyboron building blocks from readily available hydrocarbons. Combination of the benzylic perborylation with a new deborylative conjugate addition-alkylation method enables a one-pot procedure in which multiple simple precursors are combined to generate diastereopure products containing quaternary stereocenters.

SUBMITTER: Palmer WN

PROVIDER: S-EPMC5697753 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Benzyltriboronates: Building Blocks for Diastereoselective Carbon-Carbon Bond Formation.

Palmer W Neil WN Zarate Cayetana C Chirik Paul J PJ

Journal of the American Chemical Society 20170213 7

A highly diastereoselective carbon-carbon bond-forming reaction involving the tandem coupling of benzyltriboronates, enoates, and alkyl halides is described. This method was enabled by the discovery of α-diimine nickel catalysts that promote the chemoselective triborylation of benzylic C(sp3)-H bonds using B2Pin2 (Pin = pinacolate). The C-H functionalization method is effective with methylarenes and for the diborylation of secondary benzylic C-H bonds, providing ...[more]

PMID: 28156108

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