| Recently, the design and assembly of coordination polymers have been of greatinterests due to their interesting topologies and potential applications as catalyst,superconductor, magnetic, and optical materials. The generation of this type ofmolecular architecture rests on several factors, such as the metals, the solvents, thereaction conditions, the performance of the ligand, etc. In this paper, differentreaction systems have been selected to synthesize seventeen coordination polymers,in order to study on the effect factors (nature of metal, size of ligand, pH value andtemperature) of the final products at hydrothermal condition.1. We choose transition metal-oxalate acid-N-heterocyclic organic ligands asreaction system at hydrothermal condition and obtained six coordinationcompounds: [Cd2(OH)2(ox)]n (1), [Zn(ox)(Him)]n (2), [Zn(bta)2]n (3),[Zn(ox)(Hbta)2]n (4), Zn(na)2(H2O)4 (5) and Mn(in)2(H2O)4 (6). Compound 1exhibits 3-D framework with 1-D channels mainly constructed by oxalate ligand,which display novel coordination mode. 2 displays two-dimensional networkconstructed by oxalate ligand, imidazole acts as terminal ligand alternativelyextrude out two sides of the 2-D sheet. 3, containing two benzotriazolecoordination modes, display a 2-D layer structure. For compound 4, metal Zn (II)is linked to 1-D dimensional chain by oxalate ligand, with benzotriazole ligandsbeing arranged two sides of the chain. 5 and 6 are both mononuclearcoordiantion compounds with nicotinicate and isonicotinicate ligands,respectively, which are linked by Ow-H···O hydrogen bonds to form 3-Dsupramolecular network.2. Applying in situ ligand synthesis reaction, we synthesized two organiccompounds HOOC-C6H4-C7N2H5·2H2O (7), C6H4-NH-CO-CO-NH (8) and fournovel coordination compounds Cd(bibim)2(SO4)?H2O (9),[Zn(mal)(phen)(H2O)]n(10), Cd(fum)(phen)]n (11) and{[V(phen)3]2(fum)}(OH)6·18H2O (12). Organic compound 7 is obtained by thecyclization reaction between the phthalic acid and o-phenylenediamine ligandsin the presence of Mo atom. Compound 8, which is very different to compound 7,was obtained through acylation reaction of oxalic acid and o-phenylenediamineligands without metal existing in the reaction system. Compound 9 ismononuclear compound with 2, 2'-bibenzoimidazole organic ligand, which isobtained by in situ cyclization reaction. Hydrogen-bonds between 2, 2'-bibenzoiimidazoleand sulfate link the mononuclear compound to form 2-Dsupramolecular network. For compound 10, the malate, which is obtained fromthe in situ hydration reaction of maleic acid, links Zn atoms to form 1-D chainwith phen extruding out of one side of the chain as terminal ligand. The structureof compound 11 is 2-D sheet constructed by fumarate, which is synthesized byin situ isomeric transformation of maleic aicd, the phen ligands are arranged atthe two sides of the sheet. Compound 12 consist of coordination cation[V(phen)3]4+, fumarate dianion, obtained from intramolecular dehydration ofmalic acid, and lattic water molecules.3. Two coordination compounds with 1-D water chain Co(C4H4O6)(2,2'-bipy)·5H2O (13) and [Co(2,2'-bipy)3]2[V4O12]·11H2O (14) were synthesized byhydrothermal reactions. The host of compound 13 is tetradentate tartrate link themetal ions to a one-dimensional chain with 2, 2'-bipy ligands existing one sideof the chain. The lattice water molecules link each other to form 1-D water chainthrough hydrogen-bonds with the same direction as the host chain. The waterchains act as "glue" to reinforce the coordination polymeric chains forming anoverall 3-D structure. For compound 14, a part of lattic water molecules linkeach other to form 1-D "S"-like water chain, which hydrogen bond with oxygenatoms, coming from host cluster anion, to form 2-D sheet. Then, the watermolecules, which are not concerned within the water chain, further connect the2-D sheet to form 3-D supramolecular network with 1-D channels.4. Three metal-halogen compounds [PbBr2(2, 2'-bipy)]n (15), [PbBr2(Hbta)2]n (16)and [Ni(SCN)4(Hpip)2] (17) have been synthesized. Componds 15 and 16 weresynthesized at hydrothermal condition, in which Pb(II) are linked by μ2-Br-atoms to form 1-D chain with 2,2'-bipy (for 15) and benzoimidazole (for 16)alternatively extruding out the two sides of the chains as terminal ligands.Compound 17 is a mononuclear compound, synthesized at room temperature,and is connected by S···S interactions and N-H···S hydrogen bonds to form 2-Dsupramolecular sheet.5. Compound 1-11 and 15-17 all possess good fluorescence emissions. Analyzingthe principle of their emission, we can conclude that the carboxylate ligands arealmost no contribution to the coordiantion compounds emission;while theligands with planar configuration, such as phen, coordinated 2,2'-bipy etc, verycontribute to the coordiantion compounds emission.6. The redox behavior of compound 12 was investigated by cyclic voltammogram,which suggests that the redox processes are nearly reversible involving one-electron transfer V(IV/V).7. Temperature-dependent magnetic susceptibility research indacates the presenceof ferromagnetic interactions between Co(II) ions in the 1-D supramolecularchain of compound 13.8. Comparing the syntheses and the structure of all the compounds, we can obtainthe conclusion: the nature of metal ion, the size of ligands, pH value and reactiontemperature all effect on the finally products, while the definitive effect factorfor different reaction is dissimilar.
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