A novel, base-and ligand-free one pot protocol for the synthesis of fused-quinazolinone under microwave irradiation using environmentally friendly PEG-400 as a solvent has been developed. Besides benzaldehyde, various benzyl alcohols and methyl arenes were used in this protocol, which extend its synthetic applicability. Photophysical study of this highly fluorescent framework was studied by fluorescent study. DFT and ESI/MS studies were carried out to justify the proposed mechanism.