A series of 2D and 3D metal-organic frameworks based on different polycarboxylate anions and a flexible 2,2'-bis(1H-imidazolyl)ether ligand

Eight new coordination polymers, namely [Ni(L1)(BIE)] (1), [Cu(L1)(BIE)] (2), [Cu(L2)(BIE)] (3), [Co(L3)(BIE)] (4), [Cu(L4)(0.5)(BIE)] (5), [Co-2(L4)(BIE)(2)]center dot H2O (6), [Cu-5(L5)(4)(mu(3)-O)(2)(BIE)(2)(H2O)(2)] (7) and [Cu-3(L6)(2)(BIE)(2)(H2O)(3)] (8), where L1 = p-phthalate, L2 = o-phthalate, L3 oxalate, L4 = 1,2,4,5benzenetetracarboxylate, L5 m-phthalate, L6 1,3,5-benzenetricarboxylate and BIE 2,2'-bis(1Himidazolyl) ether, were successfully synthesized under hydrothermal conditions. Polymers 1 -4 display 2D layer struc.tures. 1, 2 and 3 hold the similar 4-connected 4 4-sql nets, while 4 exhibits a 3-connected 6 3hcb net. 5 possesses an unusual 4-connected Kagome net with two kinds of connected nodes. 6 shows a rare 3,4-connected (8(3))(2)(8(5).10) topology with 3-connected nodes and square-planar 4-connected nodes. 7 exhibits an alpha-Po topology based on pentanuclear Cu( II) cluster. 8 is a unique self-penetrating 2D network with 3,4-connected (6.7(2))(6.7.8)( 6(2).7.8(2).9) topology. The structural differences of 1-8 suggest the importance of polycarboxylate ligands and central metals in the network construction of the coordination polymers.