Synthesis of Chiral Tertiary Boronic Esters by Oxime-Directed Catalytic Asymmetric Hydroboration

Veronika M. Shoba, Nathan C. Thacker, Andrew J. Bochat, James M Takacs

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

Chiral boronic esters are useful intermediates in asymmetric synthesis. We have previously shown that carbonyl-directed catalytic asymmetric hydroboration (CAHB) is an efficient approach to the synthesis of functionalized primary and secondary chiral boronic esters. We now report that the oxime-directed CAHB of alkyl-substituted methylidene and trisubstituted alkene substrates by pinacolborane (pinBH) affords oxime-containing chiral tertiary boronic esters with yields up to 87 % and enantiomeric ratios up to 96:4 e.r. The utility of the method is demonstrated by the formation of chiral diols and O-substituted hydroxylamines, the generation of quaternary carbon stereocenters through carbon-carbon coupling reactions, and the preparation of chiral 3,4,4-trisubstituted isoxazolines.

Original languageEnglish (US)
Pages (from-to)1465-1469
Number of pages5
JournalAngewandte Chemie - International Edition
Volume55
Issue number4
DOIs
StatePublished - Jan 22 2016

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Oximes
Esters
Carbon
Hydroxylamines
Alkenes
Olefins
Substrates

Keywords

  • asymmetric catalysis
  • homogeneous catalysis
  • hydroboration
  • oximes
  • rhodium

ASJC Scopus subject areas

  • Chemistry(all)
  • Catalysis

Cite this

Synthesis of Chiral Tertiary Boronic Esters by Oxime-Directed Catalytic Asymmetric Hydroboration. / Shoba, Veronika M.; Thacker, Nathan C.; Bochat, Andrew J.; Takacs, James M.

In: Angewandte Chemie - International Edition, Vol. 55, No. 4, 22.01.2016, p. 1465-1469.

Research output: Contribution to journalArticle

Shoba, Veronika M. ; Thacker, Nathan C. ; Bochat, Andrew J. ; Takacs, James M. / Synthesis of Chiral Tertiary Boronic Esters by Oxime-Directed Catalytic Asymmetric Hydroboration. In: Angewandte Chemie - International Edition. 2016 ; Vol. 55, No. 4. pp. 1465-1469.
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