Directed, Remote Dirhodium C(sp3)-H Functionalization, Desaturative Annulation, and Desaturation

J Am Chem Soc. 2022 Oct 5;144(39):17989-17998. doi: 10.1021/jacs.2c07427. Epub 2022 Sep 26.

Abstract

Iminodirhodium reactive intermediates generated in situ from O-tosyloximes using Rh2(esp)2 in CH2Cl2 at rt were exploited for an agile trichotomy of challenging transformations: (1) remote C-H functionalizations using an exceptionally broad diversity of inorganic and organic nucleophiles including several unconventional examples, for example, ethers and acyl silanes; (2) desaturative annulation, a biomimetic 1,3-methylene C-C ring-closure with an overall loss of two hydrogens; and (3) directed desaturation for the acceptor-less, regioselective creation of γ,δ- or γ,δ,ε,ζ-olefins. Compared with typical iminyl transition-metal-mediated and 1,5-hydrogen atom-transfer (1,5-HAT) processes, iminodirhodium intermediates are largely underexplored, especially with respect to C(sp3)-H centers and, yet, have the potential to be transformative by virtue of their substrate breadth, regiocontrol, and elusive reaction modality. A substrate scope includes benzylic, allylic, propargylic, tertiary, and α-alkyloxy centers.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkenes
  • Catalysis
  • Ethers
  • Hydrogen*
  • Silanes*

Substances

  • Alkenes
  • Ethers
  • Silanes
  • Hydrogen