Study On The Constructions And Properties Of Coordination Compounds Based On 2-(3,5-dicarboxylphenyl)-6-carboxyl-benzimidazole

Coordination polymers(CPs),is a new type of inorganic-organic hybrid material with highly ordered structure,and it has great potential application value in many aspects,such as environmental protection,energy conversion,pharmaceutical medicine and so on.However,it is still a challenging task to construct stable complexes with ideal structure and function.Studies have shown that N-heterocyclic carboxylic acid ligands with multiple coordination sites not only have various coordination modes,but also the metal-nitrogen bond helps to improve the stability of the complexes.Therefore,in this paper,four complexes with different dimensional structures and functions were constructed by organic ligand 2-(3,5-dicarboxylphenyl)-6-carboxylbenzimidazole(H₃L)with transition metal ions Zn(?),Co(?),Mn(?)and main group metal ions Pb(?).This paper is divided into the following four chapters:Chapter 1:The concept and application prospect of CPs are briefly introduced,and the CPs constructed by benzimidazole carboxylic acid ligands as well as the basis and research progress of this thesis are introduced.Chapter 2:A two dimensional layered complex,{[H₂N(Me)₂][Zn₂(L)₂]·DMF}_n(1)was synthesized by solvothermal method using H₃L and Zn(?).The experimental results shown that complex 1 had a good adsorption selectivity for CO₂,and it also shown high selectivity and sensitivity fluorescence recognition for nitrobenzene and Cr₂O₇^2-ions.Chapter 3:A three dimensional complex with double interpenetrating layer columnar structure,{[Co(HL)(4,4'-bipy)]·DMF·2H₂O}_n(2)was synthesized by using ligand H₃L and bridging ligand 4,4'-bipydine with Co(?)under solvothermal conditions.Complex 2 has good water stability and thermal stability.The activated 2a can selectively adsorb Congo dye in water.In addition,2a also had good adsorption properties towards CO₂,and it can effectively catalyze the conversion of CO₂to cycle carbonate under mild conditions.Chapter 4:Two new complexes,[Pb(HL)(H₂O)]_n(3)and{[Mn₂(HL)₂(H₂O)₂]·3H₂O}_n(4)were synthesized by solvothermal method using ligand H₃L with Pb(?)and Mn(?),respectively.Complex 3 is a three dimensional structure with multiple active sites,and complex 4 is an one dimensional chain structure.The activated 3a showed excellent catalytic performance and cyclicity for CO₂cycloaddition reaction.There is antiferromagnetic interaction between the Mn(?)ions of complex 4.