ICT based photoacid probe for microsolvation and H-bonding assisted proton transfer process from solute to solvents

Abstract

The present work recognises 2-(3,4-Dihydroxybenzylidene)malononitrile (Hy34DC) as a photoacid and intramolecular charge transfer (ICT) probe for proton transfer process from solute to solvent at the ground and excited state. Microsolvation and intermolecular H-bonding interactions play a significant role in enhancing the proton transfer process. Solvent-dependent enhancement of proton transfer process is observed comparing the relative intensity of ICT band from UV–Vis results at ground state. Solvent-specific dual fluorescence properties of Hy34DC are also detected in solution. Polar protic solvents boost the proton transfer process from solute to solvent via intermolecular H-bonding interaction. DFT calculations are also performed to investigate the solvent-dependent solute–solvent interactions.