Mixed-Ligand Uranyl Polyrotaxanes Incorporating a Sulfate/Oxalate Coligand: Achieving Structural Diversity via pH-Dependent Competitive Effect
Mixed-Ligand Uranyl Polyrotaxanes Incorporating a Sulfate/Oxalate Coligand: Achieving Structural Diversity via pH-Dependent Competitive Effect
复制标题
掺入硫酸盐/草酸盐共配体的混合配体铀基聚轮烷：通过 pH 依赖性竞争效应实现结构多样性
DOI：
10.1021/acs.inorgchem.6b02515
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发表时间：
2017
影响因子：
4.6
通讯作者：
Shi Wei-qun
中科院分区：
文献类型：
--
作者：
Xie Zhen-ni;Mei Lei;Hu Kong-qiu;Xia Liang-shu;Chai Zhi-fang;Shi Wei-qun
混合配体系统提供了一种通过引入功能性有机或无机共配体来调节金属有机化合物的结构和性质的替代途径。在这项工作中，通过混合配体方法水热合成了五种新的掺有硫酸盐或草酸盐共配体的铀酰基聚轮烷化合物。基于C6BPCA@CB6 (C6BPCA= 1,1′-(hexan-1,6-diyl)bis(4-(carbonyl)pyridin-1-ium), CB6 = cucurbit[6]uril)配体，UPS1(UO2(L)0.5(SO4)(H2O)·2H2O,L=C6BPCA@CB6)是通过将初始水溶液pH值改变至更高而形成的酸度。所得的 UPS1 二维铀酰聚轮烷片结构基于通过 C6BPCA@CB6 拟轮烷连接体连接的硫酸铀酰带。利用草酸盐配体代替硫酸盐，通过调节反应pH和配体浓度，获得了四种含草酸盐的铀酰聚轮烷化合物UPO1–UPO4：在低pH值范围（1.47–1.89）下获得了一维链的UPO1(UO2(L)0.5(C2O4)0.5(NO3)·3H2O)。和UPO2(UO2(L)(C2O4)(H2O)·7H2O)在较高的pH值范围(4.31–7.21)下获得。通过降低草酸用量，分别在1.98的低pH值和6以上的较高pH值下获得另外两个铀酰聚轮烷网络UPO3((UO2)2(L)0.5(C2O4)2(H2O))和UPO4((UO2)2O(OH)(L)0.5(C2O4)0.5(H2O))。 UPO1-UPO4化合物通过草酸盐的pH依赖性竞争效应表现出结构多样性，代表了第一系列以有机配体作为共配体的混合配体铀酰聚轮烷。此外，还详细讨论了自组装过程及其涉及pH依赖性竞争效应的内部机制以及其他相关因素（例如试剂浓度和共配体的配位行为）。
A mixed-ligand system provides an alternative route to tune the structures and properties of metal–organic compounds by introducing functional organic or inorganic coligands. In this work, five new uranyl-based polyrotaxane compounds incorporating a sulfate or oxalate coligand have been hydrothermally synthesized via a mixed-ligand method. Based onC6BPCA@CB6 (C6BPCA= 1,1′-(hexane-1,6-diyl)bis(4-(carbonyl)pyridin-1-ium), CB6 = cucurbit[6]uril) ligand,UPS1(UO2(L)0.5(SO4)(H2O)·2H2O,L=C6BPCA@CB6) is formed by the alteration of initial aqueous solution pH to a higher acidity. The resulting 2D uranyl polyrotaxane sheet structure ofUPS1is based on uranyl-sulfate ribbons connected by theC6BPCA@CB6 pseudorotaxane linkers. By using oxalate ligand instead of sulfate, four oxalate-containing uranyl polyrotaxane compounds,UPO1–UPO4, have been acquired by tuning reaction pH and ligand concentration:UPO1(UO2(L)0.5(C2O4)0.5(NO3)·3H2O) in one-dimensional chain was obtained at a low pH value range (1.47–1.89) andUPO2(UO2(L)(C2O4)(H2O)·7H2O)obtained at a higher pH value range (4.31–7.21). By lowering the amount of oxalate, another two uranyl polyrotaxane networkUPO3((UO2)2(L)0.5(C2O4)2(H2O)) andUPO4((UO2)2O(OH)(L)0.5(C2O4)0.5(H2O)) could be acquired at a low pH value of 1.98 and a higher pH value over 6, respectively. TheUPO1–UPO4compounds, which display structural diversity via pH-dependent competitive effect of oxalate, represent the first series of mixed-ligand uranyl polyrotaxanes with organic ligand as the coligand. Moreover, the self-assembly process and its internal mechanism concerning pH-dependent competitive effect and other related factors such as concentration of the reagents and coordination behaviors of the coligands were discussed in detail.