丁铁单元自组装成伊米达酸盐边缘桥接的分子正方形:包括莫斯巴乌尔光谱学的表征
Jennifer L Hess1, Chung-Hung Hsieh, Scott M Brothers
1Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA.
Journal of the American Chemical Society
|November 15, 2011
概括
合成了新的含有伊米达酸盐的铁-酸分子方块. 这些稳定的四重复合体表现出独特的结构特征和分子识别潜力.
科学领域:
- 无机化学 无机化学 有机化学
- 协调化学 协调化学
- 超分子化学 超分子化学
背景情况:
- 铁-基复合物在各种化学和生物过程中都很重要.
- 分子方块提供独特的结构框架来容纳客分子.
- 了解这些复合物的电子和结构性质对于它们的应用至关重要.
研究的目的:
- 为了合成和表征新型的imidazolate桥接铁-nitrosyl分子正方形.
- 研究这些复合物的结构变化和分子识别能力.
- 阐明合成的四聚合物的电子性质和溶液行为.
主要方法:
- 通过氧化氧化一氧化碳从减少的铁前体中取而代之的合成.
- 使用X射线衍射分析进行结构确定.
- 通过EPR,红外光谱学,电化学和莫斯尔光谱学进行表征.
- 计算研究来探索结构异构体.
主要成果:
- 成功合成了三种含有{Fe(NO) ((2))) 的imidazolate分子正方形.
- X射线衍射揭示了铁的精确方形平面,含有意达酸盐和酸连接物.
- 由于伊米达酸盐的取向而导致的结构变化被观察到,为分子识别创造了空洞.
- 光谱和电化学数据表明,四相聚合物在溶液中的稳定性.
- 莫斯巴乌尔光谱学区分了氧化和减少的铁基复合物,四聚体类似于氧化形式.
结论:
- 含有伊米达酸盐的{Fe ((NO)) ((2))) ((9) 分子方位是稳定的,结构多样化的.
- 这些复杂物具有适合分子识别的空洞.
- 用Mössbauer光谱检测的电子性质与阴离子{Fe(NO) ((2))) ((9) 单位一致.
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