MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
Inorg Chem. 2013 Jun 3;52(11):6450-6. doi: 10.1021/ic400340y. Epub 2013 May 22.
Two isostructural 1D coordination polymers {[Ln(OAc)2(H2O)(OBPT)]·3H2O}n (HOBPT = 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol, Ln = Eu(3+), 1; Tb(3+), 3) and two discrete complexes [Ln(OAc)2(DMF)2(OBPT)] (Ln = Eu(3+), 2; Tb(3+), 4) have been synthesized in H2O-MeOH or DMF solvents, respectively. Their structures were identified by powder X-ray diffraction. Single-crystal X-ray studies for complexes 1 and 2 revealed that the coordination geometries of the Eu(3+) ions are similar and can be described as a distorted tricapped trigonal prism with six oxygen atoms and three nitrogen atoms. The difference between them is that one aqua ligand and one oxygen atom from the OBPT ligand complete the coordination sphere in complex 1, whereas two DMF molecules complete the coordination sphere in complex 2. Interestingly, the solvent-mediated, reversible crystal-to-crystal transformation between them was achieved by immersing the crystalline samples in the corresponding solvent (H2O or DMF) or by exposing them to solvent vapor. Complex 1 shows a highly selective luminescence enhancement in response to DMF in comparison to that observed in response to other examined solvents such as acetone, ethyl acetate, ethanol, acetonitrile, methanol, and THF.
两种同构的 1D 配位聚合物 {[Ln(OAc)2(H2O)(OBPT)]·3H2O}n (HOBPT = 4,6-双(2-吡啶基)-1,3,5-三嗪-2-醇，Ln = Eu(3+)，1；Tb(3+)，3) 和两个离散的配合物 [Ln(OAc)2(DMF)2(OBPT)] (Ln = Eu(3+)，2；Tb(3+)，4) 分别在 H2O-MeOH 或 DMF 溶剂中合成。它们的结构通过粉末 X 射线衍射确定。对配合物 1 和 2 的单晶 X 射线研究表明，Eu(3+)离子的配位几何形状相似，可以描述为具有六个氧原子和三个氮原子的扭曲的三角双锥。它们之间的区别在于，在配合物 1 中，一个水分子和一个来自 OBPT 配体的氧原子完成配位球，而在配合物 2 中，两个 DMF 分子完成配位球。有趣的是，通过将结晶样品浸入相应的溶剂（H2O 或 DMF）或暴露于溶剂蒸气中，可以实现它们之间溶剂介导的、可逆的晶体-晶体转变。与其他考察的溶剂（如丙酮、乙酸乙酯、乙醇、乙腈、甲醇和 THF）相比，配合物 1 对 DMF 的荧光增强具有高度选择性。
