The merger of decatungstate and copper catalysis to enable aliphatic C(sp3)-H trifluoromethylation

Nat Chem. 2020 May;12(5):459-467. doi: 10.1038/s41557-020-0436-1. Epub 2020 Mar 16.

Abstract

The introduction of a trifluoromethyl (CF3) group can dramatically improve a compound's biological properties. Despite the well-established importance of trifluoromethylated compounds, general methods for the trifluoromethylation of alkyl C-H bonds remain elusive. Here we report the development of a dual-catalytic C(sp3)-H trifluoromethylation through the merger of light-driven, decatungstate-catalysed hydrogen atom transfer and copper catalysis. This metallaphotoredox methodology enables the direct conversion of both strong aliphatic and benzylic C-H bonds into the corresponding C(sp3)-CF3 products in a single step using a bench-stable, commercially available trifluoromethylation reagent. The reaction requires only a single equivalent of substrate and proceeds with excellent selectivity for positions distal to unprotected amines. To demonstrate the utility of this new methodology for late-stage functionalization, we have directly derivatized a broad range of approved drugs and natural products to generate valuable trifluoromethylated analogues. Preliminary mechanistic experiments reveal that a 'Cu-CF3' species is formed during this process and the critical C(sp3)-CF3 bond-forming step involves the copper catalyst.

Publication types

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

MeSH terms

  • Amines / chemistry
  • Biological Products / chemistry
  • Catalysis
  • Coordination Complexes / chemistry*
  • Copper / chemistry*
  • Hydrocarbons, Fluorinated / chemistry*
  • Hydrogen / chemistry
  • Methylation
  • Molecular Structure
  • Oxidation-Reduction
  • Photochemical Processes

Substances

  • Amines
  • Biological Products
  • Coordination Complexes
  • Hydrocarbons, Fluorinated
  • Copper
  • Hydrogen