Syntheses,Crystal Structures and Luminescent Properties of Two Lanthanide Coordination Polymers Based on Bifunctional Ligand

Two lanthanide coordination polymers, [Eu（HL）（L）（H2O）2]n（1） and [Tb（H0.5L）2]n（2）, based on bifunctional 5-（1H-imidazol-1-yl） isophthalic acid（H2L）, are hydrothermally synthesized and characterized by both single-crystal and powder X-ray diffraction analyses, and FT-IR. In compound 1, the basic inorganic building unit of the coordination network is the dinuclear [Eu2（COO）6] cluster. Each [Eu2（COO）6] cluster connects four HL^- ligands and each HLligand links two [Eu2（COO）6] clusters, resulting in a 2D coordination layer. The adjacent 2 D layers are further connected via neighboring inter-layer hydrogen bonds to give a 3D supramolecular structure. In compound 2, the Tb^3＋ is coordinated to six oxygen atoms. Each Tb^3＋ ion connects six ligands and each ligand links three Tb^3＋ ions, leading to a 3D coordination polymeric network which exhibits remarkably high thermal stability up to 500℃. Furthermore, due to the successful incorporation of Tb^3＋, compound 2 displays characteristic luminescent emission in the solid state at room temperature. The combination of high thermal stability and fluorescent property of compound 2 would make it as a promising light-emitting material.

Syntheses,Crystal Structures and Luminescent Properties of Two New Zinc(Ⅱ) Complexes Based on Bifunctional Ligand

By using solvothermal method,two novel coordination polymers based on 4-（4-carboxyphen-yl）-1,2,4-triazole（Hcpt） and Zn（Ⅱ） cations,[Zn（cpt）（OH）]_n·n H_2O（FJU-32） and [Zn（cpt）（atrz）]n（FJU-33）（Hatrz = 3-amino-1,2,4-triazolate）,were synthesized and characterized by single-crystal X-ray diffraction analyses,elemental analyses,FT-IR and powder X-ray diffraction. FJU-32 crystallizes in monoclinic,space group P21/c with a = 3.7441（3）,b = 23.0384（19）,c = 11.8562（10） ？,β = 99.069（8）o,V = 1009.91（15） ？3,Dc = 1.898 g/cm3,C_9H_9N_3O_4Zn,Mr = 288.57,F（000） = 916,μ（MoKα） = 2.439 mm^（-1）,Z = 4,R = 0.0600 and wR = 0.1306 for 2412 observed reflections（I 〉 2σ（I））,and R = 0.0704 and wR = 0.1349 for all data. FJU-33 crystallizes in monoclinic space group P21/c with a = 12.7483（5）,b = 9.9922（3）,c = 9.8403（3） ？,β = 100.756（4）°,V = 1231.47（7） ？~3,Dc = 1.816 g/cm^3,C_（11）H_9N_7O_2Zn,Mr = 336.62,F（000） = 680,μ（Cu Kα） = 2.957 mm^（-1）,Z = 4,R = 0.0478 and w R = 0.1184 for 2466 observed reflections（I 〉 2σ（I））,and R = 0.0687 and w R = 0.1309 for all data. In FJU-32,Zn（Ⅱ） is coordinated to three μ3-OH groups forming an unprecedented 1D zigzag-like double chain,and the 1D double chains are connected to four neighbouring double chains by the cpt ligands to form an extended 3D porous coordination polymer. In FJU-33,the adjacent [Zn（atrz）] 2D layers are further connected by the cpt ligands via Zn–O coordinated bonds and neighboring interlayer hydrogen-bonding interactions to give rise to an overall 3D pillared layer structure. The neutron triazole group of the cpt ligand has weaker coordination ability than the triazolate anion of atrz ligand. Furthermore,FJU-32 and FJU-33 display high thermal stability up to 300 ℃,and the solid state fluorescence reveals that two new complexes are potential optical materials.

Designed Bifunctional Ligands in Cooperative Homogeneous Gold Catalysis

Over the past two decades,homogeneous gold catalysis has experienced exponential development and contributed a plethora of highly valuable synthetic methods to the synthetic toolbox.Metal–ligand cooperative catalysis is a versatile strategy for achieving highly efficient and/or novel catalysis but has seldom been explored in gold chemistry.This minireview summarizes the progress we have made in developing remotely functionalized biaryl-2-ylphosphine ligands and employing them in cooperative gold catalysis that achieves excellent catalytic efficiency or realizes previously unknown reactivities.This approach also provides new venues for implementing asymmetric gold catalysis.

Molecular Structures and Catalytical Performance in Suzuki-coupling Reaction of Novel Dipalladium Clip-shaped Complexes with Bifunctional Pyrazolate Ligands

A series of clip-shaped cationic molecular corners C1~C4(C1=[(bpy)_(2)Pd_(2)(L^(1))_(2)]^(2+),C2=[(dmbpy)_(2)Pd_(2)(L^(1))_(2)]^(2+),C3=(bpy)_(2)Pd_(2)(L^(2))_(2)]^(2+),C4=(dmbpy)_(2)Pd_(2)(L^(2))_(2)]^(2+),bpy=2,2-bipyridine,dmbpy=4,4΄-dimethyl-2,2-bipyridine)were synthesized through dipalladium complexes[(bpy)_(2)Pd_(2)(NO_(3))_(2)](NO_(3))_(2),[(dmbpy)_(2)Pd_(2)(NO_(3))_(2)](NO_(3))_(2)and bifunctional pyrazole ligands 4-(3,4-dimethoxyphenyl)-3,5-dimethyl-1H-pyrazol(HL^(1))and 4,4΄-(5-(^(1)H-pyrazol-4-yl)-1,3-phenylene)dipyridine(HL^(2)).Complexes C1~C4 were characterized by^(1)H and^(13)C NMR,electrospray ionization mass spectrometry(ESI-MS),elemental analysis,and IR spectroscopy.The X-ray diffraction analysis of C1∙2NO_(3)−revealed a Pd_(2)dimetallic clip-shaped structure which was synthesized by two bifunctional ligands doubly bridged by the[(bpy)Pd]_(2)dimetal units.Additionally,all of the complexes with NO_(3)−as counter anions exhibited high-efficiency catalytical performance in the Suzuki-coupling reaction attributed to the tunable impact and weak dinuclear Pd(Ⅱ)···Pd(Ⅱ)intramolecular bonding interaction.

Synthesis,Structure and Luminescence Properties of Dumbbell-like Silver Clusters

In this work,three stable dumbbell-shaped silver clusters 1~3,formed by a novel bifunctional ligand Ph2P-C6H4-3-C=CH,are presented.All three complexes have cage structures constructed with thirty-six silver atoms,which are templated by chloride anions.During the self-assembly process of silver acetylides,argentophilic interactions and Ag(I)-ethynide interactions are important for the formation of silver cores to yield a diversity of silver clusters.Weak molecular interactions(π-π,C-H…π,C-H…F,C-H…O)are also found in these complexes,which are crucial to stabilizing these silver clusters.Compared with simple alkynyl ligands(RC≡C-),the introduction of phosphine groups into alkynyl ligand can effectively control the undesired infinite growth of silver acetylides.The photophysical behaviors of complexes 1~3 are studied,showing intense orange roomtemperature luminescence in the solid state upon the exposure to UV light.The luminescence mainly arises from ligand-to-metal charge transfer(LMCT)and metal-cluster-centered transitions(MC)within the silver clusters.