Hong-Yang Jia

Construction of three high-dimensional supramolecular networks from temperature-driven conformational isomers

Under different temperatures, the reaction mixture of the multidentate organic ligand usy-L4 and Zn(NO3)2 + NaN3 crystallized to give three conformational isomers, namely Zn(usy-L4)(η1-N3)2 (α-1, β-2 and γ-3) (usy-L4 = N,N-dimethyl-2-(pyridin-2-ylmethylimino)ethanamine). Single-crystal X-ray diffraction analyses reveal that the conformational isomerism of three compounds 1–3 stems from the different orientations of two azide groups with η1-terminal nitrogen atom coordinating to central zinc ion in reference to the basal chelating plane of ligand usy-L4, and further resulting in different supramolecular networks with two-dimensional 44 rhombic-grid for α-1, a three-dimensional 36·418·53·6 compressed-NbO framework for β-2, and a three-dimensional “dense” 424·64 topology for γ-3. Meanwhile, three isomers may be also irreversibly converted from 1 to 2, to 3 through SC-to-SC transformation driven by temperature.

Single-crystal to single-crystal transformation from a 1-D chain-like structure to a 2-D coordination polymer on heating

The temperature-driven single-crystal to single-crystal transformation of a new erbium(III) coordination polymer with the ligand benzimidazole-5,6-dicarboxylic acid (H2bidc), {[Er(bidc)(ClO4)((H2O)3]·3H2O}n (1) to [Er(bidc)(ClO4)]n (2), has been reported and the structures of 1 and 2 were determined by X-ray crystallography. The thermal stability of compounds 1 and 2 were studied by thermogravimetric analysis (TGA). Powder X-ray diffraction experiments showed that the phase transitions described for single crystals also occur in the macroscopic powder samples and lead to monophasic products. Interestingly, with the loss of water molecules, the near infrared (NIR) emission of the Er(III) ion in compound 2 can be obviously enhanced compared to that in 1, which provides an effective strategy for enhancing the near infrared luminescence of lanthanide complexes.

Assemblies of several supramolecular networks containing quinoline-2,3-dicarboxylic acid

At low temperature, the reactions of quinoline-2,3-dicarboxylic acid (2,3-H2qldc) with ZnCl2 in three different solvents gave three 0-D mononuclear compounds respectively, namely Zn(2,3-Hqldc)2(H2O)2 (1), Zn(2,3-Hqldc)2(DMSO)2 (2) and Zn(2,3-Hqldc)2(H2O)2·C6H6 (3). At high temperature, the three corresponding reactions always produced 2-D 44 topological layer [Zn(2,3-Hqldc)2]n (4). Interestingly, compound 4 may also be constructed through the temperature-driven irreversible change in solution from 1, 2 and 3. Supramolecular structure analyses reveal that through hydrogen bonding interactions, such as O–H⋯O/C–H⋯O)/C–H⋯π/π⋯π, the mononuclear units Zn(2,3-Hqldc)2(H2O)2 (1), Zn(2,3-Hqldc)2(DMSO)2 (2) and Zn(2,3-Hqldc)2(H2O)2·C6H6 (3) as well as the 2-D layer [Zn(2,3-Hqldc)2]n (4) were further assembled into 3-D 412·63 (in 1 and 4) and 3-D 424·64 (in 2 and 3) supramolecular networks, respectively. Obviously, these results show that the reaction temperature and solvent play critical roles in directing the molecular structures and supramolecular assemblies of these low-dimensional zinc(II) compounds.

CCDC 849599: Experimental Crystal Structure Determination

Related Article: Xu-Jia Hong, Ming-Fang Wang, Hong-Yang Jia, Wei-Xing Li, Jing Li, Yi-Ting Liu, Hong-Guang Jin and Yue-Peng Cai|2013|New J.Chem.|37|933|doi:10.1039/C3NJ40783G

Poly[[tetraaquadi-μ3-oxalato-μ2-oxalato-diprasedymium(III)] dihydrate]

In the title compound, {[Pr2(C2O4)3(H2O)4]·2H2O}n, the three-dimensional network structure has the PrIII ion coordinated by nine O atoms in a distorted tricapped trigonal-prismatic geometry. The coordinated and uncoordinated water molecules interact with the carboxylate O atoms to consolidate the network via O—H⋯O hydrogen bonds.

Poly[[tetra­aquadi-μ3-oxalato-μ2-oxalato-diprasedymium(III)] dihydrate]

In the title compound, {[Pr2(C2O4)3(H2O)4]·2H2O}n, the three-dimensional network structure has the PrIII ion coordinated by nine O atoms in a distorted tricapped trigonal-prismatic geometry. The coordinated and uncoordinated water molecules interact with the carboxylate O atoms to consolidate the network via O—H⋯O hydrogen bonds.

Poly[[tetra-aquadi-μ(3)-oxalato-μ(2)-oxalato-diprasedymium(III)] dihydrate].

In the title compound, {[Pr2(C2O4)3(H2O)4]·2H2O}n, the three-dimensional network structure has the PrIII ion coordinated by nine O atoms in a distorted tricapped trigonal-prismatic geometry. The coordinated and uncoordinated water molecules interact with the carboxylate O atoms to consolidate the network via O—H⋯O hydrogen bonds.