Studies on the Configurational Stability of Tropolone-Ketone-, Ester-, and Aldehyde-Based Chiral Axes

J Org Chem. 2024 Jan 5;89(1):541-552. doi: 10.1021/acs.joc.3c02286. Epub 2023 Dec 22.

Abstract

Recent studies have revealed that tropolone-amide aryl C-C(O) rotational barriers are dramatically higher than those of analogous benzamide-based systems, and as a result, they have an increased likelihood of displaying high configurational stability. Studies on other tropolone-based chiral axes are important to assess the generality of this phenomenon. Herein, we describe a series of studies on the rotational barriers of tropolone-ketone, tropolone-ester, and tropolone-aldehyde chiral axes. These studies are complemented with computational modeling of the dynamics of these and analogous benzenoid variants to illuminate the impact that tropolone may have on aryl-C(O) configurational stability.