Synthesis of novel profluorescent nitroxides as dual luminescent-paramagnetic active probesElectronic supplementary information (ESI) available: Experimental procedures, electron paramagnetic spectra, fluorescence spectra, crystallographic parameters and NMR spectra. CCDC 1547795. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7nj01698k

• Main Authors: Coman, Anca G, Paraschivescu, Codruta C, Paun, Anca, Diac, Andreea, H dade, Niculina D, Jouffret, Laurent, Gautier, Arnaud, Matache, Mihaela, Ionita, Petre
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c7nj01698k

We describe herein the synthesis of new profluorescent nitroxides based on 2,5-disubstituted-1,3,4-oxadiazoles as fluorescent moieties and the 2,2,6,6-tetramethylpiperidine- N -oxyl radical (TEMPO) as paramagnetic probes. The synthesis and optical and electronic properties of the oxadiazole-based precursors of the profluorescent nitroxides, as well as the nitroxides and their reduced forms are also described. Physical investigations ( i.e. absorption and emission spectroscopy, cyclic voltammetry) indicate a different luminescence behaviour function to the oxadiazole substituent. A linear response to reducing agents, i.e. sodium ascorbate, monitored by fluorescence spectroscopy, suggests the possibility of using the synthesized compounds as potent active probes in detection of various analytes of interest. Profluorescent nitroxides containing 2,5-diaryl-1,3,4-oxadiazoles as fluorophore units were synthesized and characterized as actively responsive probes to reducing agents.