Sobczak Paulina, Sierański Tomasz, Świątkowski Marcin, Trzęsowska-Kruszyńska Agata, Kolińska Jolanta
Institute of General and Ecological Chemistry, Lodz University of Technology Zeromskiego 116 Lodz 90924 Poland
Łukasiewicz - Lodz Institute of Technology M. Sklodowskiej-Curie 19/27 90570 Lodz Poland.
RSC Adv. 2025 Jan 17;15(3):1514-1526. doi: 10.1039/d4ra07856j. eCollection 2025 Jan 16.
This study investigates the structure-property relationships of a series of phenylhydrazones bearing various electron-donating and electron-withdrawing substituents, such as methoxy, dimethylamino, morpholinyl, hydroxyl, chloro, bromo, and nitro groups. The compounds were synthesized, and their structures were characterized using single-crystal X-ray diffraction, powder X-ray diffraction, FTIR spectroscopy, NMR spectroscopy, and DSC. Three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy and UV-Vis spectroscopy were employed to elucidate the complex interplay between the molecular skeleton, substituents, and the resulting photophysical properties. Quantum mechanical calculations provided further insights into the electronic structure and excited-state dynamics of the investigated compounds. The phenylhydrazones exhibited emission wavelengths ranging from 438 to 482 nm, with the molecular backbone playing a crucial role in determining the emission wavelength. The incorporation of electron-donating substituents, such as methoxy and dimethylamino groups, led to enhanced fluorescence intensity, while the presence of nitro groups, resulted in complete fluorescence quenching. This comprehensive study establishes rational design principles for the development of highly emissive phenylhydrazones with tuned photophysical properties and highlights the significance of the molecular skeleton in dictating the fluorescence behavior of this class of compounds.
本研究考察了一系列带有各种供电子和吸电子取代基（如甲氧基、二甲氨基、吗啉基、羟基、氯、溴和硝基）的苯腙的结构-性质关系。合成了这些化合物，并使用单晶X射线衍射、粉末X射线衍射、傅里叶变换红外光谱、核磁共振光谱和差示扫描量热法对其结构进行了表征。采用三维激发-发射矩阵（3D-EEM）荧光光谱和紫外-可见光谱来阐明分子骨架、取代基与所得光物理性质之间复杂的相互作用。量子力学计算为所研究化合物的电子结构和激发态动力学提供了进一步的见解。苯腙的发射波长范围为438至482 nm，分子主链在决定发射波长方面起着关键作用。引入供电子取代基，如甲氧基和二甲氨基，导致荧光强度增强，而硝基的存在则导致完全荧光猝灭。这项全面的研究为开发具有可调光物理性质的高发射性苯腙建立了合理的设计原则，并突出了分子骨架在决定这类化合物荧光行为方面的重要性。
