Design, synthesis, characterization, photophysical and pH chemosensor studies of novel 2,4,6-trisubstituted pyridines

ABSTRACT

For the application in organic electronics as well as pH meters, a series of novel 2,4,6-trisubstituted pyridines have been synthesized by the reaction of substituted aromatic aldehydes and substituted 3-acetylcoumarin with ammonium acetate. The structures of all the new compounds were characterized by IR, NMR, and GC–MS analysis. The important photo physical prerequisites for organoelectronic such as optical absorption and thermal stability were determined for the synthesized molecules. Optical properties were studied by UV–visible absorption and fluorescence spectroscopy. Optical band gaps of the 2,4,6-trisubstituted pyridines were found to be around 3.01–3.06 eV as calculated from their onset absorption edge. The pH-dependent changes in the fluorescence intensity suggest that 2,4,6-trisubstituted pyridines are useful applicants in intracellular pH meters.

GRAPHICAL ABSTRACT

KEYWORDS:

• 2,4,6-Trisubstituted pyridines
• band gap
• fluorescence emission
• protonation studies

Acknowledgments

Authors thank University Sophisticated Instrumentation Center (USIC), Karnatak University, Dharwad for spectral analysis.

Additional information

Funding

One of the authors Nirmala S. Naik acknowledges UGC for providing RFSMS scholarship and also UGC-UPE New Delhi, for the financial support.