Acta Chimica Sinica ›› 2020, Vol. 78 ›› Issue (12): 1411-1417.DOI: 10.6023/A20070337 Previous Articles     Next Articles



陈光辉a,b, 何燕萍a, 张磊a, 张健a   

  1. a 中国科学院福建物质结构研究所 结构化学国家重点实验室 福州 350002;
    b 桂林理工大学 材料科学与工程学院 桂林 541004
  • 投稿日期:2020-07-31 发布日期:2020-08-11
  • 通讯作者: 何燕萍, 张健;
  • 基金资助:

Syntheses and Structural Studies of a Series of Ti4(embonate)6-based Complexes

Chen Guanghuia,b, He Yanpinga, Zhang Leia, Zhang Jiana   

  1. a State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China;
    b College of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, China
  • Received:2020-07-31 Published:2020-08-11
  • Supported by:
    Project supported by the National Natural Science Foundation of China (No. 21935010).

Metal-organic cages (MOCs) as a new type of molecular containers have attracted great interest because of their special cavities and wide applications in molecule recognition and separation, drug delivery and catalysis, etc. However, in the past decades, most researchers just devote to constructing discrete MOCs with special functions. Since many cage compounds are not soluble and stable in the solvent, the further assembly of cages into advanced materials is relatively less developed. In our previous study, we reported a water-soluble and ultrastable Ti4L6 (L=embonate) tetrahedron with coordination assembly function, which has been applied as the starting material to realize coordination assembly with different metal ions through two-step reaction. In this work, by employing the Ti4L6 cages to assemble with Mn2+, Nd3+, Ba2+ and Ca2+ ions, respectively, a series of Ti4L6-based complexes have been synthesized under different solvothermal reaction conditions, namely, (Me2NH2)9(Me4N)[Mn3(Ti4L6)2(H2O)9(DMF)6]·Guests (PTC-241, DMF=N,N-dimethylformamide); (Me2NH2)5- [Nd(Ti4L6)(H2O)2(DMF)5]·Guests (PTC-242); (Me2NH2)2[Ba4(Ti4L6)(OH)2(H2O)8(TEA)5]·Guests (PTC-243, TEA=Triethanolamine); (Me2NH2)2[Ca3(Ti4L6)(H2O)8(DEA)2]·Guests (PTC-244, DEA=Diethanolamine); (Me2NH2)2[Ca3(Ti4L6)- (H2O)15]·Guests (PTC-245). Their structures were characterized by X-ray single crystal diffraction, thermo gravimetric analyzer (TGA), infrared spectroscopy (IR) and powder X-ray diffraction (PXRD). Single-crystal analysis reveals that PTC-241 is a supramolecular homochiral architecture formed by the staggered accumulation of ΔΔΔΔ-[Ti4L6] and ΔΔΔΔ-[Ti4L6]-Mn3 cages by weak interactions (such as hydrogen bonding and π-π stacking). PTC-242 is also a supramolecular structure, in which the Ti4L6-Nd cages are linked by (Me2NH2)+ cations and ethanediamine (en) molecules via the weak N-H…O hydrogen bonding force, giving rise to a 3D H-bonding framework with a honeycomb lattice of hexagonal channels along the b axis. PTC-243 is a linear Ti4L6-Ba4 chain structure. Both PTC-244 and PTC-245 are two-dimensional (2D) Ti4L6-Ca3 layers with honeycomb-like structures. In addition, we also investigated the fluorescent properties of PTC-244 and PTC-245 in the solid state, and the results show that both of them display strong emitting bands in the visible region.

Key words: titanium-organic cage, stepwise assembly, synthesis, crystal structure