Photophysical Properties and Electronic Structure of Symmetrical Curcumin Analogues and Their BF<sub>2</sub> Complexes, Including a Phenothiazine Substituted Derivative

oleh: Emese Gál, Levente Csaba Nagy

Format: Article
Diterbitkan: MDPI AG 2021-12-01

Deskripsi

Symmetrically substituted curcumin analogue compounds possess electron donor moieties at both ends of the conjugated systems; their difluoroboron complexes were synthesized, and their structures were fully characterized. A novel compound with enhanced photophysical properties bearing phenothiazine moieties is reported. The introduction of BF<sub>2</sub> into the molecular structures resulted in bathochromic shifts both in the absorption and emission spectra, indicating that the π-conjugation was more extended than the one in the initial compounds. The solvatochromic effects were studied, which in case of the phenothiazinyl-curcumin BF<sub>2</sub> complex was the most notable. Theoretical study of the investigated compounds was carried out using DFT and TD-DFT methods to evaluate the ground state geometries and vertical excitation energies.