Syntheses, crystal structures, and properties of four transition metal complexes based on 5-nitro-8-hydroxyquinoline

Abstract

Four new complexes, [M(C₉H₅N₂O₃)₂(H₂O)₂]·CH₃OH (M = Zn(II), Cd(II) and Mn(II)) (1–3) and [Cu(C₉H₅N₂O₃)₂] (4), have been synthesized by reactions of 5-nitro-quinoline-8-yl acetate (NQA) and corresponding metal salts at room temperature and characterized by elemental analysis, IR, thermal gravimetric analysis (TGA), fluorescence measurement and single crystal X-ray diffraction. 1–3 are mononuclear, further extended to 2-D layers by hydrogen bonds. For 4, Cu²⁺ is coordinated by two N atoms and two O atoms from two NQ ligands. TGA indicates that 1–4 have good thermal stabilities. Furthermore, 1 and 2 show excellent luminescence in the solid state at room temperature.

Keywords:

• 8-Hydroxyquinoline
• Metal complexes
• Luminescence properties

Acknowledgements

This work was supported financially by the National Natural Science Foundation of China (Nos. 21001078, 21271137) and the Open Project of Key Laboratory of Advanced Energy Material Chemistry (Nankai University) (KLAEMC-OP201101).