Syntheses, structures, and magnetic properties of five coordination polymers constructed from biphenyl-3,4′,5-tricarboxylic acid and (bis)imidazole linkers

Five coordination polymers (CPs), namely {[Ni-1.5(BPT)(1,4-bib)(2)(H2O)]center dot(1,4-bib)(0.5)center dot 2H(2)O}(n) (1), {[Co-2(BPT)(1,3-bimb)(mu(3)-OH)]center dot H2O}(n) (2), {[Zn(HBPT)(1,3-bimb)]center dot H2O}(n) (3), {[Co-2(BPT)(H2BPT)(4,4'-bibp)(2)]center dot 2H(2)O}(n) (4), and [Mn-2.5(BPT)(4,4'-bibp)(2.5)(SO4)(H2O)](n) (5) (H3BPT = biphenyl-3,4',5-tricarboxylic acid, 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene, 1,3-bimb = 1,3-bis(imidazol-1-ylmethyl)benzene, and 4,4'-bibp = 4,4'-bis(imidazol-1-yl)biphenyl), were synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Complex 1 exhibits unprecedented 2D + 2D -> 3D parallel entangled networks consisting of trilayer (3,4,6)-connected (4(4).5(4).6(6).8)(5.6(4).8)(2)(5(2).6(2)) sheets. Complex 2 displays a 3D (3,10)-connected 3,10T9 net based on tetranuclear {Co-4(mu(3)-OH)(2)} clusters with the Schlafli symbol (4(18).6(24).8(3))(4(3))(2). Complex 3 shows an interesting 1D tube-like chain consisting of Zn-2(1,3-bimb)(2) loops. Complex 4 affords a 2D (4(4).6(2))-sql net constructed from {Co-2} dinuclear units. Complex 5 displays a 3D 6-connected (4(12).6(3))-pcu net consisting of alpha-Po primitive cubic nets based on {Mn-5(SO4)(2)} clusters. Moreover, magnetic studies indicate that complexes 2, 4 and 5 show antiferromagnetic properties.