New quinoline α-diimine ligands as fluorescent probes for metal ions: Ultrasound-assisted and conventional synthetic methods

► Synthesis of new emissive probes based on 8-aminoquinoline. ► Study of their effect upon Zn(II) and Cu(II) ions. ► Monitoring changes in absorption and fluorescence, complemented by calculation of metal-ligand stability constants. ► Single crystal X-ray diffraction of an 8-aminoquinoline probe bearing a ferrocene moiety.