N, O-bidentate BF2-enaminone complexes: Synthesis, electronic structure, photophysical properties, and biological behaviour. (December 2022)

• Record Type: Journal Article
• Authors: Motverov, Maxim V.; Lugovik, Kseniya I.; Vataru, Galina V.; Minin, Artem S.; Pozdina, Varvara A.; Slepukhin, Pavel A.; Benassi, Enrico; Belskaya, Nataliya P.
• Is Part Of: Dyes and pigments. Volume 208(2023)
• Publication Date: 2022-12
• Subjects: BF2-Complex -- Fluorescence -- Solid state emission -- Aggregation-induced emission enhancement (AIEE) -- Density functional theory; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2022.110848
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: Twenty-six examples of 2, 2-difluoro-3, 6-diaryl-2, 3-dihydro-1, 3, 2-oxazaborinines were synthesised at 42–98% yield from commercially available reagents with a set of simple procedures and were structurally fully characterised by 1 H, 13 C, 19 F, and 11 B NMR spectroscopy and single-crystal X-ray diffraction. Quantum chemical calculations at (Time-Dependent) Density Functional Theory ((TD)-DFT) level were performed to study structural and electronic properties of these new N, O -boron complexes with variable structures. A comprehensive experimental and computational investigation of the photophysical properties of these BF2 -complexes showed that they are emissive in solutions and have a pronounced fluorescence in the solid state (up to 100%). They also demonstrated aggregation-induced emission enhancement (AIEE) effect, with a quantum yield up to 29%, blue–green-yellow emissions and good photostability. The dynamic light scattering (DLS) experiments confirmed the formation of nanoparticles in DMSO-water and EtOH-water mixtures. Confocal laser detection revealed that these BF2 -complexes may penetrate living cells and accumulate in the endoplasmic reticulum. Graphical abstract: Image 1 Highlights: A series of new N, O –BF2 complexes were obtained and their multicolor fluorescence in solution and solid state demonstrated. Relationship between the structure and photophysical characteristic was established. The AIE phenomenon was detected in DMSO-H2 O and THF-H2 O mixture with spectroscopy and DLS technique. TD-DFT calculations revealed the peculiarities of electronic and spatial structure. Biological investigations exhibited the penetration through the cell membranes.