Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.
Dalton Trans. 2012 Feb 14;41(6):1765-75. doi: 10.1039/c1dt10931f. Epub 2011 Dec 12.
Two new flexible exo-bidentate ligands were designed and synthesized, incorporating different backbone chain lengths bearing two salicylamide arms, namely 2,2'-(2,2'-oxybis(ethane-2,1-diyl)bis(oxy))bis(N-benzylbenzamide) (L(I)) and 2,2'-(2,2'-(ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl))bis(oxy)bis(N-benzylbenzamide) (L(II)). These two structurally related ligands are used as building blocks for constructing diverse lanthanide polymers with luminescent properties. Among two series of lanthanide nitrate complexes which have been characterized by elemental analysis, TGA analysis, X-ray powder diffraction, and IR spectroscopy, ten new coordination polymers have been determined using X-ray diffraction analysis. All the coordination polymers exhibit the same metal-to-ligand molar ratio of 2 : 3. L(I), as a bridging ligand, reacts with lanthanide nitrates forming two different types of 2D coordination complexes: herringbone framework {Ln(2)(NO(3))(6)(L(I))(3)·mC(4)H(8)O(2) (Ln = La (1), and Pr (2), m = 1, 2)} as type I,; and honeycomb framework {Ln(2)(NO(3))(6)(L(I))(3)·nCH(3)OH (Ln = Nd (3), Eu (4), Tb (5), and Er (6), n = 0 or 3)} as type II, which change according to the decrease in radius of the lanthanide. For L(II), two distinct structure types of 1D ladder-like coordination complexes were formed with decreasing lanthanide radii: Ln(2)(NO(3))(6)(L(II))(3)·2C(4)H(8)O(2) (Ln = La (7), Pr (8), Nd (9)) as type III, Ln(2)(NO(3))(6)(L(I))(3)·mC(4)H(8)O(2)·nCH(3)OH (Ln = Eu (10), Tb (11), and Er (12), m, n = 2 or 0) as type IV. The progressive structural variation from the 2D supramolecular framework to 1D ladder-like frameworks is attributed to the varying chain length of the backbone group in the flexible ligands. The photophysical properties of trivalent Sm, Eu, Tb, and Dy complexes at room temperature were also investigated in detail.
设计并合成了两个新的柔性外齿双齿配体，它们分别带有两个水杨酰胺臂，配体的骨架链长度不同，分别为 2,2'-(2,2'-氧双(乙烷-2,1-二基)双(氧))双(N-苄基苯甲酰胺)(L(I))和 2,2'-(2,2'-(乙烷-1,2-二基双(氧))双(乙烷-2,1-二基))双(氧)双(N-苄基苯甲酰胺)(L(II))。这两个结构相关的配体被用作构建具有发光性质的不同镧系元素聚合物的构建块。在所合成的镧系硝酸盐配合物系列中，有十种通过元素分析、TGA 分析、X 射线粉末衍射和 IR 光谱确定的配位聚合物，通过 X 射线衍射分析确定了配位聚合物。所有配位聚合物均表现出相同的金属与配体摩尔比 2:3。L(I)作为桥联配体，与镧系硝酸盐反应形成两种不同类型的 2D 配位聚合物：人字形骨架{Ln(2)(NO(3))(6)(L(I))(3)·mC(4)H(8)O(2) (Ln = La (1)，Pr (2)，m = 1, 2)}作为类型 I；以及蜂窝状骨架{Ln(2)(NO(3))(6)(L(I))(3)·nCH(3)OH (Ln = Nd (3)，Eu (4)，Tb (5)，Er (6)，n = 0 或 3)}作为类型 II，这两种类型根据镧系元素半径的减小而改变。对于 L(II)，随着镧系元素半径的减小，形成了两种不同结构类型的 1D 梯形配位聚合物：Ln(2)(NO(3))(6)(L(II))(3)·2C(4)H(8)O(2) (Ln = La (7)，Pr (8)，Nd (9))作为类型 III，Ln(2)(NO(3))(6)(L(I))(3)·mC(4)H(8)O(2)·nCH(3)OH (Ln = Eu (10)，Tb (11)，Er (12)，m, n = 2 或 0)作为类型 IV。从 2D 超分子骨架到 1D 梯形骨架的结构逐渐变化归因于柔性配体骨架链长度的变化。还详细研究了三价 Sm、Eu、Tb 和 Dy 配合物在室温下的光物理性质。
