Synthesis, characterization, photoluminescent and thermal properties of zinc(ii) 4′-phenyl-terpyridine compounds

Abstract

Reactions between 4′-phenyl-terpyridine (L) and several Zn(II) salts (trifluoromethane sulfonate, p-toluenesulfonate, benzoate, p-hydroxybenzoate, o-hydroxybenzoate or m-hydroxybenzoate) led to the formation of the complexes [Zn(OSO₂CF₃)₂L(H₂O)] (1), [Zn(p-OSO₂PhCH₃)₂L] (2), [Zn(OCOPh)₂L] (3), [Zn(p-OCOPhOH)₂L] (4), [Zn(o-OCOPhOH)₂L] (5) and [Zn(m-OCOPhOH)₂L] (6), which were characterized by elemental analysis, ¹H NMR, ¹³C NMR, IR, single crystal X-ray diffraction and fluorescence spectroscopies. In 1, the Zn atom is hexacoordinated, with a N₃O₃ coordination environment, whereas in the remaining structures the metal atom is envisaged as possessing distorted N₃O₂ irregular trigonal bipyramidal coordination geometries. All the compounds show interesting photo-luminescent properties in solid and solution states in DMF, DMSO and methanol, which are reported along with their TG-DTA thermal decomposition processes.