Switch-on diketopyrrolopyrrole-based chemosensors for cations possessing Lewis acid character was written by Kumar, G. Dinesh;Banasiewicz, Marzena;Jacquemin, Denis;Gryko, Daniel T.. And the article was included in Chemistry – An Asian Journal in 2021.Category: pyridine-derivatives This article mentions the following:
For the first time diketopyrrolopyrroles (DPPs) have been synthesized directly from nitriles possessing (aza)crown ethers leading to macrocycle-dye hybrids. Depending on the nature of the linkage between DPP and macrocyclic ring, various coordination effects are found. The strong interaction of the cations possessing Lewis acid character such as Li+, Mg2+ and Zn2+ with 2-aminopyridin-4-yl-DPPs, leading to a bathochromic shift of both emission and absorption, as well as to strong enhancement of fluorescence was rationalized in terms of strong binding of these cations to the N=C-NR2 functionality. The same effect has been observed for protonation. Depending on the size and the structure of the macrocyclic ring the complexation of cations by aza-crown ethers plays an important but secondary role. The interaction of Na+ and K+ with 2-aminopyridin-4-yl-DPPs leads to moderate enhancement of fluorescence due to the aza-crown ethers binding. The very weak fluorescence of DPP bearing 2-dialkylamino-pyridine-4-yl substituents is due to the closely lying T2 state and the resulting intersystem crossing. In the experiment, the researchers used many compounds, for example, 2-Fluoroisonicotinonitrile (cas: 3939-14-8Category: pyridine-derivatives).
2-Fluoroisonicotinonitrile (cas: 3939-14-8) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Category: pyridine-derivatives