Simple grinding for the synthesis of monomeric, dimeric, and trimeric pyridinium salts and its photophysical studies

Abstract

Synthesis of water-soluble-substituted pyridinium cation which is attached with base sensitive fluorophore peripheral units with different inorganic counter anions under conventional/silica-supported Muffle furnace methods. Solvent-free synthetic approach has more merits than the conventional method, such as non-toxic, shorter reaction time, easy workup procedure without purification process, and higher yields. Ultraviolet-visible spectra were recorded in neutral, acidic, and alkaline medium; it showed greater red shift in alkaline medium compared with neutral and acidic pH medium.