Four anthraquinone-1,5-disulfonate-based metal complexes incorporating N-heterocyclic coligands: synthesis, crystal structures, and fluorescence

Abstract

Four new anthraquinone-1,5-disulfonate (L)-based metal complexes with N,N-bidentate chelating coligands, {[Pb(phen)₂(L)] · 4H₂O} _n (1), {[Mn₂(2,2′-bipy)₂(H₂O)₆(L)] · L · 6H₂O} (2), [Co(phen)₂(H₂O)(L)] (3), and [Zn(phen)₂(H₂O)(L)] (4) (phen = 1,10-phenanthroline and 2,2′-bipy = 2,2′-bipyridine), have been hydrothermally synthesized and were structurally characterized by single-crystal X-ray diffraction, elemental analyses, FT-IR spectra, thermogravimetric curves, and solid luminescence spectra. Structural analysis suggests that 1 is a polymeric 1D zigzag chain bridged by dianionic L. In contrast, the other three complexes have discrete centrosymmetric binuclear structure for 2 and isolated isomorphic mononuclear entities for 3 and 4, which are further assembled into 3D supramolecular networks by abundant hydrogen-bonding and/or π–π stacking interactions. Additionally, 2 and 4 exhibit favorable luminescent emissions, suggesting they are potential candidates for light emission materials.

Keywords:

• Anthraquinone-1,5-disulfonate
• Crystal structure
• Hydrogen bond
• Fluorescent property

Acknowledgments

This study was financially supported by the National Natural Science Foundation of China (grant nos. 20871092 and 20973125), the Key Project of Chinese Ministry of Education (grant no. 209003), the Program for New Century Excellent Talents in University (grant no. NCET-08-0914) and the Natural Science Foundation of Tianjin (grant nos. 10JCZDJC21600 and 10JCYBJC04800), which are gratefully acknowledged.