Synthesis,Structures And Properties Of Metal Coordination Compounds Based On Benzimidazole

The metal-organic coordination polymers have attracted more focus due to their various structures,abundant topology types and wide applications.The rational selection of organic ligands is crucial to the self-assembly of coordination polymers,we have designed and sythenised six different benzimidazole ligands in this paper.Utilizinging these ligands plus various carboxylates as mixed ligands,ten novel coordination polymers have been obtained under hydrothermal/solvothermal conditions.The crystal stuctures of these complexes have been characterized and the thermogravimetric analysis,fluorescence and catalytic activities were investigated.Moreover,the influences of metal ions,carboxylate ligands and the flexiblility of benzimidazole on the final structures and properities of these complexes have been discussed in detail.Five complexes derived from semi-rigid benzimidazole ligands(L1,L2)and carboxylate have been obtained.Complex 1 is a rare trinodal(3,4,4)-connected 3D framework with 3,4,4T78 topology;complex 2 repersents the 3D diamond structure;complex 3 exhibits a 1D chain;complex 4 shows a double nuclear compound and 5 holds a 2D(4,4)grid.Furthermore,there exist supramolecular interations in complexes 3,4 and 5.The combination of four flexible benzimidazole ligands(L3~L6)with Ag(I),Mn(II),Co(II)and diverse aromatic carboxylate ligands construct five new coordination polymers.Complex 6 shows a 1D chain;complex 7 is a binodal(4,5)-connected 3-fold interpenetrating 3D network with xah topology;complexes 8 and 10 are both sql net and expanded into 3D supramolecular with the hydrogen interations;complex 9 exhibits 2D layer structure with htb topology.All complexes display high thermal stabilities and different fluorescence properties.Complex 1,2,4,6,7 and 10 exhibit positive catalytic activities and repeatability in the degradation of methyl orange.