In 2022,Yuan, Shou; Zhang, Yuefa; Chen, Junwu; Yu, Yuan; Yue, Lingtai; Sun, Qikun; Zhang, Haichang; Xue, Shanfeng; Yang, Wenjun published an article in Advanced Optical Materials. The title of the article was 《Effectively Unlocking the Potential Molecular Room Temperature Phosphorescence of Pure Carbazole Derivatives》.Formula: C7H3BrFN The author mentioned the following in the article:
The current prevailing views are that carbazole derivatives without isomers show inferior room temperature phosphorescence (RTP) and that N-aryl carbazole derivatives exhibit no ultralong RTP in dilute film states since the distorted structures easily dissipate the excitation energy. In the current work, we present that doping N-aryl carbazole derivatives with heteroatoms and/or heavy halogen into PMMA at the mol. level by thermoplasticizing solution-cast films can achieve ultra-long-lived (>1 s) and highly-efficient (>36%) mol. RTP without the need of crystallization and isomer doping. Unlike isomer-doped crystals that almost all emit yellow RTP, the RTP colors of doped PMMA films depend on the mol. structures of carbazole derivatives Also, we can realize highly efficient and long-lived red fluorescence afterglow via persistent Forster resonance energy transfer from RTP emission to fluorescent emitter. These colorful afterglow polymer films exhibit an ultra-long (>20 h) photo-activation pattern memory effect. This work has challenged existing exptl. results and relative RTP mechanisms, providing a reasonable processing strategy for manifesting and enhancing the deserved RTP properties of organic doped polymers. The experimental part of the paper was very detailed, including the reaction process of 4-Bromo-2-fluorobenzonitrile(cas: 105942-08-3Formula: C7H3BrFN)
4-Bromo-2-fluorobenzonitrile(cas:105942-08-3) is used as a reagent in the synthesis of picolinamide derivatives as a novel class of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitors.Formula: C7H3BrFN 4-Bromo-2-fluorobenzonitrile is also used in the preparation of fluorinated CB2 receptor agonists for PET imaging.
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts