Coligand syntheses, crystal structures, luminescence and photocatalytic properties of five coordination polymers based on rigid tetracarboxylic acids and imidazole linkers

Five coordination polymers (CPs) with distinct structures, namely, [Cu(H(2)tptc)(1,4-bidb)](n) (1), {[Co-2(tptc)(1,3,5-tib)(H2O)]center dot 7H(2)O}(n) (2), {[Ni(tptc)(0.5)(1,3-bimb)]center dot H2O}(n) (3), {[Zn(qptc)(0.5)(1,4-bimb)]center dot 3H(2)O}(n) (4), and {[Zn(qptc)(0.5)(1,3-bimb)]center dot H2O}(n) (5) (H-4 tptc = terphenyl-3,3 '',5,5 ''-tetracarboxylic acid, H(4)qptc = quaterphenyl-3,3''',5,5'''-tetracarboxylic acid, 1,4-bidb = 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene, 1,3,5-tib = 1,3,5-tris(1-imidazol-yl)benzene, 1,3-bimb = 1,3-bis(imidazol-1-ylmethyl)benzene, and 1,4-bimb = 1,4bis(imidazol-1-ylmethyl)benzene), have been synthesized through a mixed ligand strategy. Complex 1 features a new 3D (4,6)-connected net with a Schlafli symbol of (4(2).6(4))(4(2).6(8).7.8(4)). Complex 2 displays a 3D 2-fold interpenetrated framework with an unprecedented (3,3,4,4)-connected (6.8(2))(2)(6(2).8(3).10)(6(2).8(4)) topology. Complex 3 exhibits a (3(2).6(2).7(2))-kgm layer featuring a 2D + 2D -> 3D packing supramolecular structure interweaved through [Ni(1,3-bimb)] lock knots. Complex 4 shows an unprecedented 3D (4,4)-connected 86 net. Complex 5 is also a 2D + 2D -> 3D supramolecular structure featuring kgm sheets hinged together through [Zn.1,3-bimb)] lock knots. In addition, the luminescence properties of 4 and 5 have been investigated. Moreover, complexes 1-3 show relatively good photocatalytic activities for methylene blue (MB) dye degradation in aqueous solution under UV light.