3-D Hydrogen-bonded networks of metal complexes with chelidamic acid and 1,10-phenanthroline: syntheses, structures, and optical properties

Abstract

The title complexes, (C₁₂H₈N₂) ⋅ [La(C₇H₃NO₅)(C₇H₄NO₅) ⋅ 3H₂O] ⋅ 1.75H₂O (1), (C₁₂H₈N₂) ⋅ [Pr(C₇H₃NO₅)(C₇H₄NO₅) ⋅ 3H₂O] ⋅ 2H₂O (2), (C₁₂H₈N₂)[Nd(C₇H₃NO₅)(C₇H₄NO₅) ⋅ 3H₂O] ⋅ 2.25H₂O (3), and (C₁₂H₈N₂) ⋅ [Fe(C₇H₃NO₅)(C₇H₄NO₅)] ⋅ 2H₂O (4), were synthesized and characterized by single-crystal X-ray diffraction. The crystal structures of 1–3 reveal that they are isomorphous, among which the metal atoms are all nine-coordinate with distorted tricapped trigonal prismatic coordination geometries. The Fe is six-coordinate with a distorted octahedron by two chelidamic acid ligands in 4. Complexes 1–4 are formed into 3-D networks by H-bonds and π–π stacking interactions. The fluorescence spectra of 1–3 were investigated and all exhibit strong luminescence.

Keywords:

• 1,10-Phenanthroline
• Chelidamic acid
• Crystal structure
• Optical properties
• Syntheses

Acknowledgments

We gratefully acknowledge the financial support provided by the NSF of China (20801026), the NSF of Jiangxi Province (2008GQC0036), the Aviation Science Foundation of China (2008ZF56012), Science Foundation of State Key Laboratory of Structural Chemistry (20100015), and Open Fund of the Key Laboratory of Nondestructive Testing, Ministry of Education, Nanchang Hangkong University (ZD200929007).