Extended Aromatic and Heteroaromatic Ring Systems in the Chalcone-Flavanone Molecular Switch Scaffold.

Previous work on the o-hydroxychalcone/flavanone molecular switching scaffold showed that simple substitutions alter the pH range in which rapid interconversion occurs. Herein, more impactful structural modifications were performed via alteration of the characteristic phenyl rings to alternative aromatic systems. It was determined that the scaffold was still viable after these changes and that the range of accessible midpoint pH values was markedly increased.

Impact of mono- and disubstitution on the colorimetric dynamic covalent switching chalcone/flavanone scaffold.

The effect of aryl substitution on various aspects of the interconversion of ortho-hydroxychalcones and flavanones has been studied using multiple spectroscopic techniques. Derivatization of the core scaffold predictably alters the midpoint pH of this equilibration process suggesting its viability for application as a functional colorimetric molecular switch.

Towards a dynamic covalent molecular switch: substituent effects in chalcone/flavanone isomerism.

Chalcone/flavanone interconversion occurs facilely under aqueous alkaline conditions making it a promising scaffold for the development of a covalent molecular switch. In this study, a single methoxy substituent is shown to have a significant impact on the equilibrium dynamics of this reaction; this impact is dependent on the site of substitution.