Delivering 2-Aryl Benzoxazoles through Metal-Free and Redox-Neutral De-CF3 Process

J Org Chem. 2021 Oct 1;86(19):13548-13558. doi: 10.1021/acs.joc.1c01619. Epub 2021 Sep 16.

Abstract

An unexpected cleavage of the Csp3-CF3 bond of CF3-hydrobenzoxazoles has been disclosed, affording a range of 2-aryl benzoxazoles under metal-free and redox-neutral conditions. This transformation has demonstrated broad substrate scope and good compatibility of functional groups. 2-Aryl benzothiazole and 2-aryl benzoimidazole could be smoothly assembled in the same manner. On the basis of preliminary mechanistic studies, base initiated and aromatization driven β-carbon elimination was considered to be the key step for the formation of 2. This reaction offers an alternative, facile, and sustainable route to access important 2-aryl benzoxazole motifs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzoxazoles*
  • Carbon
  • Catalysis
  • Oxidation-Reduction
  • Palladium*

Substances

  • Benzoxazoles
  • Palladium
  • Carbon