LAUSR

A series of novel 2-(4-(acridin-9-ylamino)phenyl)isoindoline-1,3-dione derivatives were designed and synthesized namely 2-(4-(4-methoxyacridin-9-ylamino)phenyl)isoindoline-1,3-dione [S1], 2-(4-(3-chloroacridin-9ylamino)phenyl)isoindoline-1,3-dione [S2], 2-(4-(2-fluor oacridin-9ylamino)phenyl)isoindoline-1,3-dione [S3], 2-(4-(1,4-dichloroacridin-9ylamino) phenyl)isoindoline-1,3-dione [S4]. The photophysical, thermal properties of these compounds were characterized by the spectroscopic and thermographic method. The absorbance and fluorescence spectra of these derivatives were recorded in different solvents to understand the role of solute and solvent interaction. The compounds showed high thermal stability with thermal decomposition temperatures at 5% weight loss in a range of 250–287 °C. Compared with these compounds, donor groups containing derivatives exhibited excellent properties as fluorescent compounds. Computational studies were done using DFT (Density Functional Theory) G09 software (B3LYP/6-311G++V(d,p)) basis sets in order to calculate the optical band gap and FMO (Frontier Molecular Orbital) energies. The chemical stability of the four derivatives was determined by means of chemical hardness (η) using HOMO-LUMO energies.