| The aim of this thesis is the synthesis of chiral and novel porous POM based inorganic-organic hybrid compounds by using different kinds of flexible and unsymmetrical organic ligands through covalent linkage and/or molecular interaction. The study on synthetic conditions and rules for these new compounds and the exploration of relationships between structures and properties for these new compounds are also carried out.Twenty-eight new coordination compounds have been synthesized on the basis of hydrothermal technique and/or water solution synthesis methods and structurally characterized by elemental analyses, IR, XRPD, TG and single crystal X-ray diffractions. The thermal stabilities, fluorescent activity and et al. of these compounds have been studied.1. A series of chiral POM-based inorganic-organic hybrid compounds have been constructed by using the flexible bbi ligand, [V10O26]4-, [VxOy]n- chain and Cu, Co, Ni and Zn without any chiral auxiliary. [Cu(bbi)2V10O26][Cu(bbi)]2·H2O (1a) [Cu(bbi)2V10O26][Cu(bbi)]2·H2O (1b) [Ni2(bbi)2(H2O)4V4O12]·2H2O (2a) [Ni2(bbi)2(H2O)4V4O12]·2H2O (2b) [Co(bbi)(H2O)V2O6] (3a) [Co(bbi)(H2O)V2O6] (3b) [Zn-2(bbi)2(V3O9)(OH)]·H2O (4) [Zn2(bbi)2(V4O12)] (5) [Zn(bbi)(V2O6)] (6) bbi = 1,4-bis(1H-imidazol-1-yl)butaneThe various conformations of achiral ligand, helical vanadate chains and polyoxometalate with cage structure, which benefit the formation of chiral polyoxometalate-based compounds. The non-covalent interactions, such as the hydrogen bond interactions and Cu–O interactions, may play crucial roles in the process of the chirality preservation and spontaneous resolution when the chirality is extended into the homochiral 3D networks. The successful isolation of these species not only produces intriguing examples of enantiomerically pure architectures but may also provide a rational strategy for synthesis of chiral POM-based compounds by using achiral ligands and POM helical units.2. A series of supramolecular isomers have been obtained by using (Mo8O26)4-, flexible bbi ligand, Cu(NO3)2 and Et3N at different pH values under hydrothermal conditions. [H2bbi][CuII(bbi)2(β-Mo8O26)] (7) [CuII(bbi)2(H2O)(β-Mo8O26)0.5] (8) [CuII(bbi)2(α-Mo8O26)][CuI(bbi)]2 (9) [CuIICuI(bbi)3(α-Mo8O26)][CuI(bbi)] (10) [CuI(bbi)]2[Cu2I(bbi)2(δ-Mo8O26)0.5][α-Mo8O26]0.5 (11) [CuI(bbi)][CuI(bbi)(θ-Mo8O26)0.5] (12)We believed that various copper-organic units which are formed by bbi ligands combined with CuII/CuI cations, octamolybdates with different types and coordination modes, and the nonbonding interactions between polyanions and copper-organic units are important for the formation of the different structures. With step by step increase of the amount of organic amine, we have achieved the transformation of CuII ions into CuI ones in different degrees in POMs-based MOFs for the first time. The function of organic amine may be not only as a reducer but also as a buffering agent to reduce the crystallization speed, which is in favor of forming the similar products (such as supramolecular isomers). The successful isolation of these species maybe will provide a calculable clue for the supramolecular isomerism in POMs-based MOFs, which may help to understand the structure-property relationship of POMsbased MOFs. Further research is ongoing to prepare novel supramolecular isomers and explore their valuable properties. More importantly, the combination of these three important research fields, namely, in situ synthesization, supramolecular isomerism, and polyoxometalate chemistry, opens up new possibilities in pursuit of multifunctional materials.3. We have designed and synthesized eight compounds based on Keggin POM, Hfcz and different transition metal under hydrothermal conditions. [Zn(Hfcz)(H2O)3](H3fcz)(SiMo12O40)·3H2O (13) [Cd2(Hfcz)6(H2O)2](SiMo12O40)·H2O (14) [Co2(Hfcz)2(SiW12O40)](H3fcz)2(SiW12O40)·10H2O (15) [Ni2(Hfcz)4(H2O)2](SiW12O40)·5H2O (16) [Ag4(Hfcz)2(SiMo12O40)] (17) [CuICuII(CuIIfcz)2(H2O)5(PMo)10<sup>VIMo2VO40)]·6H2O (18) [Cu2I(CuIIfcz)2(H2O)2(PMo8VIV3VV3IVO42)]·6H2O (19) [Cu4L4PW12O40]·6H2O (20) (L = 1,3-di(1H-1,2,4-triazol-1-yl)propan-2-ol)The results of 13-17 indicate that differentmetal ions can form various metal–organic units and different metal–organic units, and polyanions with different coordination modes are linked to each other through non-covalent interactions and/or covalent connections to obtain different dimensionalities of compounds. For 18 and 19, we have developed a rational approach to the synthesis of POM-based open MOFs by combination of POMs and deliberately designed macrocations. Polyanions with different sizes and coordination modes have great influences on the ultimate structures of compounds. Compound 20 is a new type of (4,8)-connected 3D POM-based MOF using an in situ-generated ligand by C–C bond cleavage and reduction reaction under the presence of [PW12O40]3- polyanions, Cu2+ ions and Et3N in hydrothermal conditions, in which copper cations act as square planar four-connected nodes and Keggin polyanions act as cubical eight-connected nodes. To our knowledge, it represents the highest connected topological network via covalent linkages for the polyoxometalate systems.4. We have designed and synthesized a series of new N-donor and carboxylate ligands. And eight entangled net compounds with Zn or Cd metal (clusters) have been synthesized on the basis of these new ligands. An unprecedented (6,8)-connected self-penetrating network, a (3,12)-connected 3D MOF, an 8-connected self-penetrating network with the new topological type and a series of interesting topological nets showing polyrotaxane- and polycatenane-like motifs have been constructed. The study on synthetic conditions and rules for these new compounds, topological analyses, interaction of adjacent molecules, influence on the ultimate structures from ligand's conformation and auxiliary ligand, and the exploration of relationships between structures and properties for these new compounds are also carried out. [Zn2.5L(bdc)2.5]·H2O (21) [Zn8(μ3-OH)4(oba)6(bbi)(H2O)2] (22) [Zn3(bpimb)(oba)3] (23) [Cd2(bimb)2(L1)2] (24) [Cd(bpimb)0.5(L2)(H2O)] (25) [Zn5(bpib)2(L3)4(OH)2(H2O)2] (26)[Zn(bpib)0.5(L4)] (27) [Cd(bbi)(L4)] (28) bbi = 1,4-bis(1H-imidazol-1-yl)butane bpimb = 1,4-bis((2-(pyridin-2-yl)-1H-imidazol-1-yl)methyl)benzene bimb = 1,4-bis((1H-imidazol-1-yl)methyl)benzene bpib = 1,4-bis(2-(pyridin-2-yl)-1H-imidazol-1-yl)butane L = 1-((4'-((pyridin-3-yloxy)methyl)biphenyl-4-yl)methyl)pyridinium-3-olate H2oba = 4,4'-oxydibenzoic acid H2L1 = 4-((4-(dihydroxymethyl)phenoxy)methyl)benzoic acid H2L2 = 4,4'-methylenebis(oxy)dibenzoic acid H2L3 = 3,3'-methylenebis(oxy)dibenzoic acid H2L4 = 4,4'-(2,2'-oxybis(ethane-2,1-diyl)bis(oxy))dibenzoic acid... |
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