Title:Solvatochromic, Photophysical and DFT Studies of Newer 1-(2-
oxo-2-(2-oxo-2H-chromen-3-yl)ethyl)pyridin-1-ium Bromide and
1-methyl-3-(2-oxo-2-(2-oxo-2H-chromen-3-yl)ethyl)-1H-imidazol-
3-ium Bromide Synthesized under Microwave Irradiation
Volume: 12
Issue: 3
Author(s): Atul S. Patil, Raosaheb S. Patil, Vikas S. Patil and Pramod P. Mahulikar*
Affiliation:
- School of Chemical Sciences, KBC North Maharashtra University, Jalgaon 425001, India
Keywords:
Microwave-assisted synthesis, photophysical, solvatochromism, Lippert-Mataga plot, DFT, theoretical simulation.
Abstract:
Background: Pyridinium and imidazolium-based compounds show diverse applications
with basic skeleton designs in order to achieve improved optical and thermal behavior.
Aim: The aim of the study was to design and develop a greener, efficient protocol towards
newer pyridinium and imidazolium compounds, and investigate optical, solvatochromic,
thermal, and theoretical properties.
Objectives: The purpose is to study the optical properties of pyridinium and imidazolium
compounds, for which we illustrate the solvent polarity effect on the absorption and emission
behavior as a function of orientation polarizability and ET(30) solvent parameters. The
study focuses on thermal stability and computes the molecular orbital orientation and HOMO-
LUMO energies using theoretical simulation by the DFT approach.
Methods: The structures were confirmed by FT-IR, Mass, 1H NMR and 13C NMR, and optical
properties were investigated using a UV-Visible spectrophotometer and fluorometer.
The thermal behavior was investigated using thermal gravimetric analysis, and molecular
orbital orientation and energies were determined using GAUSSIAN 16 software.
Results: The newer compounds with good thermal stability and optical behavior have been
synthesized and characterized. The study interprets the intermolecular electron transfer
amongst the molecules and the effect of solvents on their excitation and emission properties.
The experimental and theoretical study illustrates the optical, thermal, and electronic
properties of both compounds.
Conclusion: The present work describes the solvatochromic optical behavior of pyridinium
bromide and imidazolium bromide synthesized by a microwave-assisted, greener and efficient
strategy. The solvatochromic study interprets the presence of non-specific solutesolvent
interactions. The photophysical, thermal, and DFT study revealed that both pyridinium
and imidazolium compounds are used for optoelectronic applications. Moreover, the
work could be helpful to researchers for developing new skeletons for optoelectronic applications.