十二甲基基-克洛索-十二甲基 ((2-)
T Peymann1, C B Knobler, S I Khan
1Contribution from the Department of Chemistry and Biochemistry, University of California Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095-1569, USA.
Journal of the American Chemical Society
|July 18, 2001
概括
在这项研究中,合成了基金属盐的十二基基-密-十二基2-) 离子,发现它们由于交联基团而具有令人惊的低水溶性. 这些发现为团的结构性质及其与子的相互作用提供了洞察力.
科学领域:
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- dodecahydro-closo-dodecaborate(2-) 离子 (closo-B(12) H(12)(2-)) 是一个研究得很好的团.
- 集群的功能化,如氧化,可以显著改变它们的特性和潜在应用.
- 了解功能化集群的金属盐的可溶性和结构特征对于它们的合成和利用至关重要.
研究的目的:
- 为了合成和表征各种金属,,和盐的十二基-密封-二甲酸.2-) 离子.
- 为了研究这些新型盐的水溶性.
- 用X射线晶体学阐明它们溶解性行为的结构基础.
主要方法:
- 使用过氧化合成二甲-二甲-二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二甲二二甲二甲二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二
- 其他金属 (Li,Na,K,Rb), ([NH(4) ](2) 1), ([PPN](2) 1) 和 ([H(3) O](2) 1) 盐的沉.
- 通过感应合等离子体原子发射光谱法 (ICP-AES) 确定水溶性.
- 用单晶X射线晶体学对四种金属盐进行固态表征.
主要成果:
- 成功合成了Cs(2) 1和随后的其他金属,,和盐.
- 观察到金属盐的水溶性令人惊地低,这与从具有基基团的二离子衍生的盐的预期相反.
- 金属盐的水溶性随着阴离子半径 (A(+) 的减少而降低,的水溶性略有异常.
- [H) 3O) 2O) 1和 (NH) 4) 2O) 1盐是水不溶和盐的罕见例子.
- X射线晶体学揭示了复杂的网络,其中二离子的基团与性金属酸交联,形成聚合盐.
- 阴离子协调数因阴离子半径而异,从Cs{+}和Rb{+}的十个到Na{+}的六个.
- dodecahydroxy-closo-dodecaborate(2-) 离子的核心几何在不同的金属盐中保持一致.
结论:
- 在十二基-密度-二甲基酸离子上的悬挂氧基团作为交联联体,导致其金属盐的水溶性较低.
- 观察到的低溶解度归因于固态中形成了广泛的键和离子协调网络.
- 集群的结构完整性保持不管反,突出了密闭酸框架的稳定性.
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