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Updated: Oct 17, 2025

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Photophysical properties of a boron analogue of coumarin
Huayi Wang1, Briana R Schrage, Kana Takematsu
1Department of Chemistry, University of Akron, Akron, Ohio 44325-3601, USA. ziegler@uakron.edu.
Abstract:
In this report, we present a study into the structure and electronic properties of difluoroboronsalicylaldoxime (DFBS), a boron-based structural analog of coumarin. The modification of the heterocyclic ring of coumarin with boron results in a compound with similar structural parameters and molecular orbitals to coumarin. DFT and TDDFT calculations reveal a significant stabilization of the LUMO in DFBS; this is supported by a ∼40 nm red shift of the lowest electronic transition in the absorption spectrum. Interestingly, DFBS is emissive, while unmodified coumarin is effectively non-radiative. Comparisons between DFBS, emissive coumarin variants, and unmodified coumarin suggest that the charge transfer character of the transition contributes to the fluorescence.
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