State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, P. R. China.
J Am Chem Soc. 2017 Nov 22;139(46):16845-16851. doi: 10.1021/jacs.7b09463. Epub 2017 Nov 7.
We have successfully constructed a tetrahedral TiL cage with calixarene-like coordination-active vertices. It further features high solubility and stability in HO and DMF/HO solution, affording an interesting stepwise assembly function with other metal ions. Through trapping of different amounts of Co or Ln ions, the TiL tetrahedra can be organized into various dimensional architectures, including a TiL-Co cage, a TiL-Ln cage, a TiL-Ln chain, and a three-dimensional TiL-Ln framework. An unusual mixed-valence phenomenon was observed in the TiL cage, whose Ti compositions were adequately identified by electron spin resonance and X-ray photoelectron spectroscopy analyses. More remarkably, the calixarene-like oxygen vertices of the TiL cage can also be used for the recognition of C-symmetric dye molecules through N-H···O hydrogen bonding. Accordingly, driven by visible light, selective and efficient homogeneous photodecomposition of acid blue 93 and alkali blue 4B were successfully achieved. Therefore, this work not only represents a milestone in constructing symmetric Ti-based cages with interesting coordination assembly function but also provides a new method for preparing technologically important soluble photoactive cages.
我们成功构建了具有杯芳烃状配位活性顶点的四面体形 TiL 笼。它在 HO 和 DMF/HO 溶液中具有高的溶解度和稳定性，提供了有趣的分步组装功能，可与其他金属离子进行配位。通过捕获不同量的 Co 或 Ln 离子，TiL 四面体可以被组装成各种维度的结构，包括 TiL-Co 笼、TiL-Ln 笼、TiL-Ln 链和三维 TiL-Ln 骨架。在 TiL 笼中观察到了一种不寻常的混合价态现象，其 Ti 组成通过电子自旋共振和 X 射线光电子能谱分析得到了充分的鉴定。更值得注意的是，TiL 笼的杯芳烃状氧顶点也可以通过 N-H···O 氢键用于识别 C 对称染料分子。因此，在可见光的驱动下，成功实现了酸性蓝 93 和碱性蓝 4B 的高效选择性均相光解。因此，这项工作不仅代表了构建具有有趣配位组装功能的对称 Ti 基笼的一个里程碑，而且为制备具有重要技术意义的可溶性光活性笼提供了一种新方法。
