Construction Of Coordination Polymers Assembled From Copper (I) And N-donor Ligands

The molecular design and controllable synthesis of functional complexes andcoordination polymers have been a serious problem in the field of inorganic chemistry.To solve this problem, it will not only be propitious to enrich the theoretical andexperimental research of synthetic chemistry, but also can offer new ideas of designingand synthesis of inorganic-organic hybrid compounds which have specific structuresand functions. People have got used to obtaining coordination polymers by solutiondiffusion methods or direct hydrothermal reactions of metal salts and ligands. However,studies of designing an assembly system of host-guest cluster-based coordinationpolymers with solvothermal in situ organic reactions are less reported.In this thesis, we chose cuprous salts to react with varied N-donor bridge ligandsunder the condition of solvothermal in situ organic reactions. The in situ-generatedorganic guests under solvothermal conditions seemed more effective to impede theinterpenetration, so that we got a series of multi-dimensional coordination polymerswith rhombic channels. It is these porous frameworks that make the compoundsfunctional and reactable. The study results are briefly described as follows:1. Solvothermal reactions of Cu2（OH）2CO3with1,2-bis（4-pyridyl）ethane （bpa） or1,2-bis（4-pyridyl）ethene （bpe） and aryliodides in a mixed solvent of acetonitrile andaqueous ammonia afforded eight arylamine-solvated [Cu₂I₂]-based coordinationpolymers：{[Cu₂I₂（bpa）₂]·aniline}_n（1）,{[Cu₂I₂（bpa）₂]· o-toluidine}_n（2）,{[Cu₂I₂（bpa）₂]·m-toluidine}_n（3）,{[Cu₂I₂（bpa）₂]·p-toluidine}_n（4）,{[Cu₂I₂（bpe）₂]·aniline}_n（5）,{[Cu₂I₂（bpe）₂]·o-toluidine}_n（6）,{[Cu₂I₂（bpe）₂]·m-toluidine}_n（7）,{[Cu₂I₂（bpe）₂]·p-toluidine}_n（8）.In-situ reduction of Cu^IIand in-situ amination of iodobenzene occurredsimultaneously in our case. At the presence of N-donor ligands, Cu^IIsalts underwent aredox process under solvothermal conditions to produce Cu^Icompounds. Cu^IImay bereduced by ligands and/or iodide （derived from the conversion of iodobenzene to aniline） and the resulting Cu^Imay combine iodides to afford the [Cu₂I₂] species. The latter wascaptured by ligands to yield [Cu₂I₂]-based frameworks. These compounds werecharacterized by single-crystal X-ray crystallography, IR spectra, elemental analysis,thermogravimetry and solid fluorimetry. These compounds all have a two-dimensional（4,4） topological network with an approximate dimension of1.2nm×2.5nm. Eachlayer is further stacked via π-π interactions to form a3D structure with1D rhombicchannels occupied by the guest molecules which are in situ generated through Ullmanncoupling reactions of aryliodides with ammonia. The thermal and photoluminescentproperties, adsorption and separation properties of these products were investigated.Upon excitation at ca.350nm, these compounds exhibited strong photoluminescencewith emission maxima at the range of600nm⁷00nm.2. Under different temperature conditions, solvothermal reactions between cuproushalides,1,4-bis（imidazol-1-yl）-butane （bimb） and corresponding aromatic halidesafforded three complexes with quite different frameworks which contain varied copperclusters:{[Cu₂I₂（bimb）₂]·iodobenzene}_n（9）,{[Cu₂I₂（bimb）][CuI（bimb）_0.5]}n（10）,{[CuBr（bimb）][Cu（bimb）Br]}_n（11）.The solvothermal reactions of CuI, iodobenzene and bimb at150°C and170°Cafforded compound9and10, respectively. Compound9has a two-dimensional （4,4）topological network in which every rhombic [Cu₂I₂] dimer acts as a planarfour-connected node to link the other neighboring four equivalent ones via bimb bridges.Each layer is further stacked by π-π interactions to form a3D structure with1D rhombicchannels occupied by the guest iodobenzene molecules. Compound10has a quitedifferent two-dimensional structure which contains two kinds of copper clusters [Cu₂I₂]and [Cu₄I₄]. On the other hand, the solvothermal reactions of CuBr, bromobenzene andbimb at150°C afforded compound11with a one-dimensional chain structure. Thesecompounds were characterized by single-crystal X-ray crystallography, IR spectra,elemental analysis, thermogravimetry and solid fluorimetry. We also investigated thephotoluminescent properties of9¹1in the solid state at room temperature. Compound9and10all exhibited strong photoluminesecence at635nm when excited at340nmwith some intensity difference, while11showed an emission maxima at480nm when excited at380nm. The results did provide interesting insights into temperature effectson the construction of cluster-based coordination polymers.