Synthesis and photochemical reaction of benzo[a]quinoxalino[2, 3‐c]phenazine dyes. (25th August 2017)

• Record Type: Journal Article
• Authors: Podsiadły, Radosław; Sokołowska, Jolanta; Kolińska, Jolanta; Grzelakowska, Aleksandra
• Is Part Of: Coloration technology. Volume 133:Number 6(2017)
• Page Start: 498
• Page End: 505
• Publication Date: 2017-08-25
• Subjects: Color -- Periodicals; Color in the textile industries -- Periodicals; Dyes and dyeing -- Periodicals; 667
• DOI: 10.1111/cote.12300
• Languages: English
• ISSNs: 1472-3581

Abstract

Abstract : Novel dyes based on the benzo[ a ]quinoxalino[2, 3‐ c ]phenazine skeleton and necessary intermediates (benzo[ a ]phenazine‐5, 6‐diones) were synthesized. The heterocyclic dyes and benzo[ a ]phenazine‐5, 6‐diones were characterized using 1 H nuclear magnetic resonance (NMR) spectroscopy and chemical ion (CI) mass spectrometry. Their spectral properties, such as absorption and emission spectra and fluorescence quantum yield, were also measured. Experimental results demonstrated that photolysis of benzo[ a ]quinoxalino[2, 3‐ c ]phenazine dyes in 2‐propanol and cyclohexene oxide leads to dihydro derivatives. The same product is formed during irradiation of dye/iodonium salt photoredox pairs in monomers. These compounds absorb incident light at longer wavelength and act as in situ sensitizers. Thus, when a composition was irradiated with a xenon lamp through a 395 cutoff filter, higher conversion was achieved than under monochromatic light.