Hydrothermal Synthesis, Crystal Structures and Photoluminescence of Two Novel Metal-organic Supramolecular Frameworks Based on Mixed Ligands of Dipyrazino[2,3f:2'3'-h]quinoxaline and Pyridine-2,5-dicarboxylic Acid

• 来源期刊: 中国化学(英文版)
• 年，卷（期）: 2008,（9）
• 页码范围: 1611-1618
• 页数: 8页
• 语种: 英文

摘要

Two novel metal-organic frameworks [Zn2(DlXl)2(2,5-pda)2(H2O)2]·2H2O (1) (dipyrazino[2,3f2'3'-h]quinoxaline=Dpq) and [Cd2(Dpq)2(2,5-pda)2]·2H2O (2) (pyridine-2,5-dicarboxylic acid=2,5-H2pda) have been obtained from hydrothermal reactions of two different metal(II) nitrates with the same mixed ligands Dpq and 2,5-H2pda,and structurally characterized by elemental analyses,TG,IR spectroscopy,and single-crystal X-ray diffraction analyse.Single-crystal X-ray analyses show that the metal ions are bridged by different coordination modes of 2,5-pda to form a dimer in 1,2D rhombic grid in 2,respectively.In the compound 1,adjacent dimers are packed through hydrogen bonds and π-π aromatic stacking interactions to form a distorted a-Po supramolecular structure.In the compound 2,adjacent polymer layers are further linked by hydrogen bonds to form a distorted a-Po 3D supramolecular framework stabilized by π-π stacking interactions.The different structures of compounds 1 and 2 illustrate the influence of the metal ions and ligands on the self-assembly of polymeric coordination architectures.In addition,the title compounds exhibit blue emission in the solid state at room temperature.