Effect of anions on architectures of transition metal complexes with 1,4-bis (1,2,4-triazol-1-yl)butane

Reaction of transition metal(II) salts with 1,4-bis(1,2,4-triazol-1-yl)butane (btb) formed a series of coordination polymers, [Cu(btb)Cl-2] (1), [Cu(btb)(2)]Br-2 (2), [Cu(btb)(2)(H2O)(2)](ClO4)(2) (3), [Cu (btb)(0.5)(Ac)(2)] (4), [Ni(btb)(H2O)(3)(SO4)] (5), [Ni(btb)(3)](ClO4)(2) (6), [Ni(btb)(3)](NO3)(2) (7), [Co(btb) (H2O)(3)(SO4)] (8), [Co(btb)(2)(NCS)(2)]center dot H2O (9), and [Co(btb)(1.5)(bdc)(H2O)] (10) (bdc(2-) = 1,4-benzenedicarboxylate). These compounds were characterized by single-crystal X-ray diffraction. 1 displays a 1D linear chain and further constructs a 3D supramolecular structure via C-H center dot center dot center dot Cl hydrogen bonds. 2 possesses a 2D helical layer structure. The layers stacked in an AB fashion are linked by C-H center dot center dot center dot Br hydrogen bonds, forming a 3D supramolecular structure. 3 has a threefold interpenetrating diamondoid network with unique helical channels. 4 shows a 1D chain, in which dimeric [Cu-2(Ac)(4)] units are bridged by btb ligands. 7 exhibits a threefold interpenetrating alpha-polonium cubic porous architecture comprising of triple-stranded helices. 10 shows a 3D metal-organic framework constructed from btb and bdc(2-)ligands. Structural results for the complexes 1-10 and reported works show that anions Cl-, Br-, ClO4-, Ac-, SO42-, NO3-, NCS- and bdc(2-) play an important role in the assembly of transition metal complexes with 1,4-bis(1,2,4-triazol-1-yl)butane.