Construction And Properties Of Coordination Polymers With Small Organic Ligands

Recently,great interest has emerged in the construction and study of coordination polymers(CPs)due to their structural diversity and potential applications in optics,electricity,adsorption/separation,magnetism,catalysis,etc.In this disseration,eleven CPs based on small organic ligands(cyanoacetic acid,6,6-Dimethyl-3-oxabicyclo[3.1.0]hexane-2,4-dione(DOHD),1,1-cyclopropanedicarboxylic acid(H₂CDA),1,1-cyclobutanedicarboxylic acid(H₂CBA))have been synthesized and characterized.The properties of luminescent probe,magnetism and catalysis for conversion of CO₂ are thoroughly investigated.The main works have been carried out in this dissertation as followings:1.A novel zinc-organic framework was synthesized through an in situ generated tetrazole ligand(1).1 has high thermal stability,p H stability(1-13)and solvent stability(ten common solvents).1 can serve as a recyclable luminescence sensor to efficiently detect harmful Cr₂O₇^2-/Cr O₄^2-and trifluralin.Besides,1 exhibits excellent catalytic ability for the cycloaddition of CO₂ with epoxides,and shows great recycle performance.2.Three transition metal complexs(2-4)were constructed based on H₂CDA ligand.The metal ions form[M₂]clusters through?₂-O,which are further linked by CDA^2-to generate 2D sheet structure.The luminescence property of 2 and magnetism of 3 and 4 have been investigated.3.A transition metal complex was constructed through in situ hydrolysis of DOHD ligand(5).5 was composed of[Cu₃O]cluster.The results indicated that 5exhibit catalytic ability for the cycloaddition of CO₂ with epoxides,and can be reused for at least three rounds.4.Three rare earth metal complexs(6-8)were constructed based on H₂CDA ligand through adjusting the reaction temperature,solvent,p H and metal salts.6-8were composed of wheel-like[Ln₁₈]clusters second building units(SBU),which are linked to six neighbouring wheels to generate a 2D ordered honeycomb array.6shows high-sensitivity luminescence sensing to Mn O₄^-,and can be reused at least three times with almost no change in luminescent intensity.Magnetic measurements of complexes 7 and 8 have been carried out,finding that 7 has a large magnetocaloric effect of 47.30 J kg^-1 K^-1(?H=7.0 T at 2 K).Besides,7 and 8 can catalyze the cycloaddition of CO₂ to epoxides under mild conditions and with negligible loss in catalytic performance.5.Three rare earth cluster-based coordination polymers(9-11)were synthesized based on H₂CBA ligand.[Ln₄O₄]cubane clusters self-assemble into an infinite chain by sharing vertex,which is further linked to adjacent chains through H₂CBA ligand,resulted in a honeycomb arrayed 3D framework.9 possesses excellent water stability,and can act as a luminescence sensor to selectively and sensitively detect quercetin with the limit of detection(LOD)as low as 0.23 ppm.Compared with HPLC-MS method,9 was used to determine the content of quercetin in onion skin and apple peel samples in the range of 0–300 ppm with satisfactory result.Furthermore,a portable9 test paper is also developed and expected to be applied in practice.To our knowledge,10 is the first example of MOFs as luminescent sensor for quercetin.As for 10 and 11,the properties of magnetism and catalysis are investigated.10 has a large magnetocaloric effect of 49.20 J kg^-1 K^-1 at 2 K for?H=7.0 T.10 and 11 are the first examples of MOFs-based catalysts for chemical fixation of CO₂ with aziridines at room temperature(25°C).