| The synthesis and characterization of metal-organic polymer have attracted much attention, due to their enormous variety of interesting structural topologies and wide potential applications as functional materials. 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, ({[Zn4(BTDA)2(bpp)2]·3.5H2O}n (1),{[Zn2(BTDA)(bix)]·H2O}n (2), {[Zn2(BTDA)(bpe)1.5(H2O)3]·H2O}n (3), [Zn2(HBTDA)(m3-OH) bpy]n (4), [Cd2(BTDA)(bpa)2(H2O)]n (5), [Cd2(BTDA)(bpp)2(H2O)2]n (6), {[Cd4(BTDA)2(bix)2(H2O)2]·4.5H2O}n (7),{[Co2(BTDA)(bpe)1.5(H2O)3]·H2O}n (8), {[Co2(BTDA)(bpy)1.5(H2O)3]·H2O}n (9),{[Ni3(BTDA)2(bpe) (H2O)6]·6H2O}n (10)), have been hydro(solvo)thermally synthesized through the reaction of flexible carboxylic acid:2,2'3,3'-benzophenone tetracarboxylic acid (2,2'3,3'-BTDA) with divalent transition metal salts in the presence of ancillary nitrogen ligands (bpa= 1,2-bis(4-pyridyl)ethane, bpe=1,2-bis(4-pyridyl)ethene, bpp= 1,3-bi(4-pyridyl)propane, bix=1,4-bis(imidazol-1-ylmethyl)benzene, and bpy= 4,4'bipyridine). These complexes charactered with IR, X-ray single crystal diffraction etc. The properties of these complexes such as fluorescence, magnetism and thermal stability have been studied.Due to various coordination modes and conformations of the versatile 2,2',3,3'-BTDA ligand and co-ligands, these complexes exhibit structural and dimensional diversity. In compounds 1-5,8 and 9, M-BTDA (M=Zn, Cd or Co) ribbons are connected together through bpp, bix, bpe, bpy and bpa, respectively, to form metal-organic sheets, which are then united together to generate 3D supramolecular structures through inter-layer hydrogen bonding, C-H…π, orπ…πinteractions. In the structure of 4 and 9, the ribbon is formed from interlaced of coaxial meso-helical Zn(Co)-HBTDA chains. Compound 6 features a 3D metal-organic framework in which [Cd2(BTDA)]n meso-helices are bridged by bpp ligands to exhibit a (2,6,2)-connected self-penetrating network with the Schlafli symbol(12)·(42129164)·(4)2.Compound 7 also exhibits a 3D metal-organic framework in which [Cd2(BTDA)]n layers are connected by pillared bix ligands to yield a (4,4,8)-connected network with the Schlafli symbol (416·612)·(44·62)·(44-62)2. Compound 10 exhibits a 3D (3,3,4)-connected network structure with the Schlafli symbol (7-102)2·(73)2·(74·10·11). Compounds 1 and 7 display intense blue fluorescence emissions at 460 and 465 nm, respectively, and may be suitable as excellent candidates of blue fluorescent materials. Compound 8 and 9 exhibit weak antiferromagnetic interaction, and the compound 10 exhibits strong ferromagnetism coupling. |
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