Synthesis and characterisation of anthracene-based fluorophore and its interactions with selected metal ions

An anthracene-based novel ligand (L), 9,10-bis((4,6-dimethylpyrimidin-2-ylthio)methyl)anthracene, was synthesised and fully characterised. Interactions of the ligand with selected metal ions, Hg(II), Cu(II), Ag(I), Pb(II), Zn(II), Ni(II), Co(II), and Cr(III), were spectroscopically investigated. Of the examined metal ions, both Hg(II) and Cu(II) showed responses in both UV–Vis and fluorescent spectroscopy towards the ligand in acetonitrile solution. Spectroscopic titration indicated that the ligand forms complexes with the two metal ions in 1:1 and 1:2 ratios, respectively. DFT calculations revealed that Hg(II) binds possibly with two pairs of donor-set {SN} of the ligand to form a mononuclear complex in a distorted planar geometry whereas Cu(II) forms likely a binuclear complex in a tetrahedral geometry in which each Cu(II) is further coordinated with possibly two acetonitrile molecules.

Graphical abstractAn anthracene-based novel ligand derived from, 9,10-bis((4,6-dimethylpyrimidin-2-ylthio)methyl)anthracene, shows selectively fluorescent recognitions in acetonitrile towards both Hg(II) and Cu(II) ions among the investigated metal ions, Hg(II), Cu(II), Ag(I), Pb(II), Zn(II), Ni(II), Co(II), and Cr(III).Figure optionsDownload full-size imageDownload as PowerPoint slide