Stationary and time-resolved spectra analysis of pyrazoloquinoline derivatives with pyridyl moiety

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2018-03, Vol.193, p.492-498
• Main Authors: Grabka, Danuta, Kolbus, Anna, Danel, Andrzej, Kucharek, Mateusz, Szary, Karol
• Format: Article
• Language: English
• Subjects: 1H-pyrazolo[3,4-b]quinoline; CT fluorescence; Emission; Fluorescent dye
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2017.12.066

Two derivatives of pyrazoloquinoline with pyridyl moiety: 6-N,N-dimethyl-3-phenyl-1-(2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (DMA-1PPhPQ) and 6-N,N-dimethyl-1,3-(di-2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (DMA-1,3PPQ) were synthesized with commercial substrates. The theoretical characterization of both compounds was done. Geometry optimizations give not flat structure with the first absorption band at the wavelength about 390nm for both compounds. Several electro-optical parameters were also calculated. The optical properties of DMA-1PPHPQ and DMA-1,3PPQ were investigated by ultraviolet-visible spectroscopy and stationary as well as time-resolved fluorescence. The fluorescence maximum and fluorescence quantum yield are strongly dependent on solvent polarity function. Results indicate CT fluorescence for both compounds. Because of high emission the investigated pyrazoloquinoline derivatives can be potential candidates for fabrications of electroluminescent devices. [Display omitted] •New high emissive derivatives of pyrazolo[3,4-b]quinoline with pyridyl moiety was synthesized.•DMA-1PPhPQ and DMA-1,3PPQ show strong fluorescence in nonpolar and medium-polar solvents with quantum yield equal or near 1.•DMA-1PPhPQ and DMA-1,3PPQ are potential candidates for optoelectronic application.