Dimensionality of luminescent coordination polymers of magnesium ions and 1,1'-ethynebenzene-3,3',5,5'-tetracarboxylic acid modulated by structural inducing agents.

Zhu-Xi Yang,Yin Qian,Xiao-Ming Ren,Jing-Wei Yu,Wen-Wei Zhang,Lu Zhai

doi:10.1039/c8ra04875d

Zhu-Xi Yang, Yin Qian + Show 4 more

Open Access

https://doi.org/10.1039/c8ra04875d

Copy DOI

Journal: RSC advances	Publication Date: Jan 1, 2018
Citations: 5	License type: CC BY 3.0

Affiliation: Nanjing Tech University, Nanjing University

Abstract

Solvothermal reactions of aromatic 1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylic acid (H4EBTC) and Mg2+ salts in the presence of different supporting ligands afforded the coordination polymers [Mg(H2EBTC)(DMF)2(H2O)2] (1), [Mg3(HEBTC)2(H2O)4]·solvent (2) and [Mg2(EBTC)(H2O)5]·solvent (3). The crystal structures of 1–3 were determined by the single crystal X-ray diffraction technique, where CP 1 showed a one-dimensional zigzag MgO6 coordination octahedral chain structure; 2 exhibited a two-dimensional MgO6 coordination octahedral framework with trinuclear [Mg3(COO)6] SBUs, and 3 featured a three-dimensional MgO6 coordination octahedral framework with binuclear [Mg2O(COO)2] SBUs. The various structures in CPs 1–3 of Mg2+ ions with the H4EBTC ligand were ascribed to the conformational flexibility and the coordination mode diversity of the H4EBTC ligand. Interestingly, the zwitterionic supporting ligand 2-aminoterephthalic acid or 4-aminobenzenesulphonic acid played a vital role in the initial formation process of nuclear crystals but only as a structural induction agent, which modulated the dimensionality of these Mg2+-based CPs. Additionally, the three CPs emitted bright blue luminescence at ambient conditions, and the emission lifetimes and absolute quantum yields were also investigated.

Highlights

As an emerging class of crystalline solids with intrinsically wellorganized host structures, functional coordination polymers (CPs) have attracted extensive research interest in the areas of inorganic chemistry, coordination chemistry, crystal engineering and materials science.[1,2,3,4,5] In this context, the structural design and controllable synthesis of functional CPs have become some of the main themes of researchers in recent years, and researchers have explored various synthetic strategies to achieve target CPs with the desired structure and functionality
We have been exploring the synthesis approach and photoluminescence properties of CPs of Mg2+ ion with the p-electron-rich alkynefunctionalized tetracarboxylic acid ligand 1,10-ethynebenzene3,30,5,50-tetracarboxylic acid (H4EBTC);[25] previous studies have demonstrated that when the H4EBTC ligand is partly or fully deprotonated, it can act as an excellent phosphor, and it simultaneously emits ligand-based uorescence and phosphorescence within a colorless Mg2+-based CP at room temperature.[25]
CP 1, [Mg(H2EBTC)(DMF)2(H2O)2], was obtained under the same reaction conditions as those used for the preparation of a Mgbased CP, [Mg(H2EBTC)(DMF)2], which we previously reported[25] except that 2-aminoterephthalic acid (2-APA) was added during the synthesis of 1

Summary

Introduction

As an emerging class of crystalline solids with intrinsically wellorganized host structures, functional coordination polymers (CPs) have attracted extensive research interest in the areas of inorganic chemistry, coordination chemistry, crystal engineering and materials science.[1,2,3,4,5] In this context, the structural design and controllable synthesis of functional CPs have become some of the main themes of researchers in recent years, and researchers have explored various synthetic strategies to achieve target CPs with the desired structure and functionality.

Results

Conclusion