A General Strategy to Enhance Donor-Acceptor Molecules Using Solvent-Excluding Substituents
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Updated: Dec 31, 2025

Separation of Aldehydes and Reactive Ketones from Mixtures Using a Bisulfite Extraction Protocol
Published on: April 2, 2018
Conner A Hoelzel1, Hang Hu2,3, Charles H Wolstenholme1
1Department of Chemistry, Pennsylvania State University, University Park, PA, 16802, USA.
Abstract:
While organic donor-acceptor (D-A) molecules are widely employed in multiple areas, the application of more D-A molecules could be limited because of an inherent polarity sensitivity that inhibits photochemical processes. Presented here is a facile chemical modification to attenuate solvent-dependent mechanisms of excited-state quenching through addition of a β-carbonyl-based polar substituent. The results reveal a mechanism wherein the β-carbonyl substituent creates a structural buffer between the donor and the surrounding solvent. Through computational and experimental analyses, it is demonstrated that the β-carbonyl simultaneously attenuates two distinct solvent-dependent quenching mechanisms. Using the β-carbonyl substituent, improvements in the photophysical properties of commonly used D-A fluorophores and their enhanced performance in biological imaging are shown.
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