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

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. 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. UV–visible spectra were recorded in different pH; it showed greater red shift in alkaline medium compared with lower pH.