Setyawati I A, Liu S, Rettig S J, Orvig C
Department of Chemistry, University of British Columbia, Vancouver, Canada.
Inorg Chem. 2000 Feb 7;39(3):496-507. doi: 10.1021/ic991170j.
The reactions of potentially hexadentate H2bbpen (N,N'-bis(2-hydroxybenzyl)-N,N'-bis(2-pyridylmethyl)-ethylenediamine, H2L1), H2(Cl)bbpen (N,N'-bis(5-chloro-2-hydroxybenzyl)-N,N'-bis(2-pyridylmethyl)ethylenediamine, H2L2), and H2(Br)bbpen (N,N'-bis(5-bromo-2-hydroxybenzyl)-N,N'-bis(2-pyridylmethyl)ethylenediamine, H2L3) with Ln(III) ions in the presence of a base in methanol resulted in three types of complexes: neutral mononuclear ([LnL(NO3)]), monocationic dinuclear ([Ln2L2(NO3)]+), and monocationic trinuclear ([Ln3L2(X)n(CH3OH)]+), where X = bridging (CH3COO-) and bidentate ligands (NO3-, CH3COO-, ClO4-) and n is 4. The formation of a complex depends on the base (hydroxide or acetate) and the size of the respective Ln(III) ion. All complexes were characterized by infrared spectroscopy, mass spectrometry, and elemental analyses; in some cases, X-ray diffraction studies were also performed. The structures of the neutral mononuclear [Yb(L1)(NO3)], dinuclear [Pr2(L1)2(NO3)(H2O)]NO3.CH3OH and [Gd2(L1)2(NO3)]NO3.CH3OH.3H2O, and trinuclear [Gd3(L3)2(CH3COO)4(CH3OH)]ClO4.5CH3OH and [Sm3(L1)2(CH3COO)2(NO3)2(CH3OH)]NO3.CH3OH.3.65H2O were solved by X-ray crystallography. The [LnL(NO3)] or [Ln2L2(NO3)]+ complexes could be converted to [Ln3L2(X)n(CH3OH)]+ complexes by the addition of 1 equiv of a Ln(III) salt and 2-3 equiv of sodium acetate in methanol. The trinuclear complexes were found to be the most stable of the three types, which was evident from the presence of the intact monocationic high molecular weight parent peaks ([Ln3L2(X)n]+) in the mass spectra of all the trinuclear complexes and from the ease of conversion from the mononuclear or dinuclear to the trinuclear species. The incompatibility of the ligand denticity with the coordination requirements of the Ln(III) ions was proven to be a useful tool in the construction of multinuclear Ln(III) metal ion arrays.
在甲醇中，在碱存在的情况下，潜在的六齿配体H2bbpen（N,N'-双（2-羟基苄基）-N,N'-双（2-吡啶甲基）乙二胺，H2L1）、H2(Cl)bbpen（N,N'-双（5-氯-2-羟基苄基）-N,N'-双（2-吡啶甲基）乙二胺，H2L2）和H2(Br)bbpen（N,N'-双（5-溴-2-羟基苄基）-N,N'-双（2-吡啶甲基）乙二胺，H2L3）与Ln(III)离子反应生成了三种类型的配合物：中性单核（[LnL(NO3)]）、单阳离子双核（[Ln2L2(NO3)]+）和单阳离子三核（[Ln3L2(X)n(CH3OH)]+），其中X = 桥联（CH3COO-）和双齿配体（NO3-、CH3COO-、ClO4-）且n为4。配合物的形成取决于碱（氢氧化物或乙酸盐）以及相应Ln(III)离子的大小。所有配合物均通过红外光谱、质谱和元素分析进行了表征；在某些情况下，还进行了X射线衍射研究。通过X射线晶体学解析了中性单核[Yb(L1)(NO3)]、双核[Pr2(L1)2(NO3)(H2O)]NO3·CH3OH和[Gd2(L1)2(NO3)]NO3·CH3OH·3H2O以及三核[Gd3(L3)2(CH3COO)4(CH3OH)]ClO4·5CH3OH和[Sm3(L1)2(CH3COO)2(NO3)2(CH3OH)]NO3·CH3OH·3.65H2O的结构。通过在甲醇中加入1当量的Ln(III)盐和2 - 3当量的乙酸钠，[LnL(NO3)]或[Ln2L2(NO3)]+配合物可转化为[Ln3L2(X)n(CH3OH)]+配合物。发现三核配合物是这三种类型中最稳定的，这从所有三核配合物质谱中完整的单阳离子高分子量母峰（[Ln3L2(X)n]+）的存在以及从单核或双核向三核物种的容易转化中可以明显看出。配体齿合度与Ln(III)离子配位要求的不相容性被证明是构建多核Ln(III)金属离子阵列的有用工具。
