Complexation of metal ions with the novel 2-hydroxy-1-naphthaldehyde-derived diamine Schiff base carrying a macrobicyclic moiety with N2O2S2 mixed donor in acetonitrile-dichloromethane

A new Schiff base containing a macrobicyclic moiety was designed and synthesized by reaction of the corresponding macrobicyclic diamine compound and 2-hydroxy-1-naphthaldehyde. The influence of metal cations such as Zn2+, Mn2+, Fe2+, Fe3+, Co2+, Ni2+ and Pb2+ on the spectroscopic properties of the 2-hydroxy-1-naphtyl group linked to the macrobicyclic moiety with N2O2S2 mixed donor was investigated in acetonitrile-dichloromethane solution (9.5/0.5) by means of absorption and emission spectrometry. Emission spectra undergo a marked blue shift and enhancement of naphtyl fluorescence in the presence of Fe3+ and Zn2+. The presence of Pb2+, Mn2+, Fe2+, Co2+ and Ni2+ caused a quenching of naphtyl fluorescence. Especially, the quenching was higher than 90% in case of the interaction of Ni2+ and Co2+ with the ligand. The results of spectrophotometric and spectrofluorimetric titration experiments disclosed the complexation properties of the novel ligand with Zn2+, Co2+ and Ni2+ cations.

Graphical abstractA new Schiff base was synthesized by reaction of the corresponding macrobicyclic diamine compound and 2-hydroxy-1-naphthaldehyde. The influence of metal cations such as Zn2+, Mn2+, Fe2+, Fe3+, Co2+, Ni2+ and Pb2+ on the spectroscopic properties of the Schiff base was investigated by means of absorption and emission spectrometry.Figure optionsDownload full-size imageDownload as PowerPoint slide