| The crystal engineering of coordination polymers has not only gained great recognition as an important interface between synthetic chemistry and materials science but also provides a solid foundation to understand how molecules can be organized and functions can be achieved. Recently, the design of metal-organic polymer with excellent properties that combine with porosity, magnetism, luminescence, or optoelectronic effects has become one of the major challenges in the pursuit of multifunctional materials. Much work of the research has focused on the optimization design of the ligands and rational choice of the metals, in which the transition metal elements and based carboxyl ligands with especial structure is a good choice.In this paper, a series of new mental-organic polymers, namely,({[Cd2(2,3-TDPA)(H2O)3]-H2O}n (1),{[Cd2(2,3-TDPA)(bpe)(H2O)3]}n (2),{[Cd2(2,3-TDPA)(bix)]}n (3),{[Cd2(2,3-TDPA)(bpg)(H2O)4]-3H2O}n (4){[Zn4(2,3-TDPA)2(bpy)2(H2O)11]-4H2O}n (5)[Cu(2,3-SDPA)0.5(2,2’-bpy)]-H2O (6),[Zn2(2,3-SDPA)(2.2’-bpy)2(H2O)2]-3H2O (7),[Zn2(2,3-SDPA)(4,4’-bpy)]-3H2O (8),[Cd2(2,3-SDPA)(4,4’-bpy)1.5(H2O)2](9), Zn,.5(3,4-HSDPA)(bpy),.5(H2O)4(10)), have been hydro(solvo)thermally synthesized through the reaction of a series of V-shaped aromaticity multicarboxylate acid ligands:2.3.2’,3’-thiaphthalic acid (2,3,2’,3’-TDPA),2,3,2’.3’-Sulfonyldiphthalic acid (2,3’,2,3’-SDPA),2.3.3’.4’-Sulfonyldiphthalic acid (2,3’.3,4’-SDPA)with divalent transition metal salts in the presence of ancillary nitrogen ligands (bix=1,4-bis(imidazo]-1-ylmethyl)benzene, bpe=1,2-bis(4-pvridyl)ethene. bpg=meso-α.β-bi(4-pyridyl).4-bpy=4.4’-bipyridine.2-bpy=2,2’-bipyridine). These complexes charactered with IR, X-ray single crystal diffraction etc. The properties of these complexes such as fluorescence and thermal stability have been studied.The ligands containing flexible backbones are among the most important types of orcanic licands because their flexibility and conformational freedom allow for greater structural diversities. In complexes1,2and3, rod-shaped Cd-chain SBUs have been formed. For1, such rod-shaped SBUs are linked together through tdpa4-itself to form a metal-organic layer, and then such layers are linked by π…πinteractions to form a three-dimensional supramolecular structure. For2and3, such metal-organic SBUs are further associated together by bpe or bix ligands in four orientations to form a robust3D metal-organic network, respectively. The Schlafli symbol are (2·4·5)(32·42·5·6·103·11)(2) and (415·630)(43)2(3), respectively. In compound4, a3D Cd-tdpa metal-organic network is accomplished through tdpa4-anion ligands, and further stabilized by bpg. The Schlafli symbol is(5·82)2(52·83·9)(52·8). In complex5, zinc atoms are bridged by tdpa4-anion ligands to form infinite Zn-tdpa chains and the adjacent chains are further linked by π…π, s…π and C-H…π interactions to form a three-dimensional supramolecular structure. Both complex6and7show metal-organic chain structures, and the adjacent chains are further linked by π…π7and C-H…π interactions, hydrogen bonds and π…π interactions to form3D supramolecular structure. In complex8, Zn-chain SBUs are linked together through4,4’-bpy ligands in four orientations to form a3D metal-organic network. In compound9, a3D Cd-sdpa metal-organic network is accomplished through sdpa4" anion ligands, and further stabilized by4,4’-bpy in six orientations. In the structure of10, an unusual compound Zn1.5(Hsdpa)(bpy)1.5(H2O)4comprising two isolated coordination polymers has been obtained by hydrothermal reactions, in which electronegative helical channels of a3D host framework A [Zn(Hsdpa)(bpy)(H2O)2]-are filled with the guest electropositive infinite1D polymer chains B [Zn0.5(bpy)0.5(H20)2]+. Compounds1,3and4display intense blue fluorescence emissions around450nm. and may be suitable as excellent candidates of blue fluorescent materials. |
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