Troponoid Atropisomerism: Studies on the Configurational Stability of Tropone-Amide Chiral Axes

Org Lett. 2019 Apr 5;21(7):2412-2415. doi: 10.1021/acs.orglett.9b00707. Epub 2019 Mar 14.

Abstract

Configurationally stable, atropisomeric motifs are an important structural element in a number of molecules, including chiral ligands, catalysts, and molecular devices. Thus, understanding features that stabilize chiral axes is of fundamental interest throughout the chemical sciences. The following details the high rotational barriers about the Ar-C(O) bond of tropone amides, which significantly exceed those of analogous benzamides. These studies are supported by both experimental and computational rotational barrier measurements. We also report the resolution of an axially chiral α-hydroxytropolone amide into its individual atropisomers, and demonstrate its configurational stability at physiological pH and temperatures over 24 h.

Publication types

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

MeSH terms

  • Amides / chemical synthesis*
  • Amides / chemistry
  • Models, Molecular
  • Molecular Structure
  • Stereoisomerism
  • Tropolone / analogs & derivatives*
  • Tropolone / chemical synthesis
  • Tropolone / chemistry

Substances

  • Amides
  • Tropolone
  • tropone