Ligand-Controlled Regiodivergent Enantioselective Rhodium-Catalyzed Alkene Hydroboration

Andrew J. Bochat, Veronika M. Shoba, James M. Takacs

Research output: Contribution to journalArticle

Abstract

Regiocontrol in the rhodium-catalyzed boration of vinyl arenes is typically dominated by the presence of the conjugated aryl substituent. However, small differences in TADDOL-derived chiral monophosphite ligands can override this effect and direct rhodium-catalyzed hydroboration of β-aryl and β-heteroaryl methylidenes by pinacolborane to selectively produce either chiral primary or tertiary borated products. The regiodivergent behavior is coupled with enantiodivergent addition of the borane. The nature of the TADDOL backbone substituents and that of the phosphite moiety function synergistically to direct the sense and extent of regioselectivity and enantioinduction. Twenty substrates are shown to undergo each reaction mode with regioselectivity values reaching greater than 20:1 and enantiomer ratios reaching up to 98:2. A variety of subsequent transformations illustrate the potential utility of each product.

Original languageEnglish (US)
Pages (from-to)9434-9438
Number of pages5
JournalAngewandte Chemie - International Edition
Volume58
Issue number28
DOIs
StatePublished - Jul 8 2019

Fingerprint

Regioselectivity
Rhodium
Alkenes
Olefins
Ligands
Boranes
Phosphites
Enantiomers
Substrates
4,4,5,5-tetramethyl(1,3,2)dioxaborolane

Keywords

  • asymmetric catalysis
  • homogeneous catalysis
  • hydroboration
  • regiodivergent reactions
  • rhodium

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Cite this

Ligand-Controlled Regiodivergent Enantioselective Rhodium-Catalyzed Alkene Hydroboration. / Bochat, Andrew J.; Shoba, Veronika M.; Takacs, James M.

In: Angewandte Chemie - International Edition, Vol. 58, No. 28, 08.07.2019, p. 9434-9438.

Research output: Contribution to journalArticle

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