Versatile Schiff-base hydrazone fluorescent receptors: Synthesis, spectroscopy and complexation studies

► Four emissive acyclic ligands (1-4) have been synthesized and characterised. ► The interaction with Cu2+ and Zn2+ was explored in solution (UV-Vis and emission spectroscopy). ► For comparative purposes, the coordination ability was explored in gas phase (MALDI-MS spectrometry).