Synthesis and Characterization of Cobalt(II) and Zinc(II) Coordination Polymers Constructed from Bis(isophthalic acid) and Bis(1,2,4-triazole) Linkers

Six new coordination polymers containing Co(II) and Zn(II), formulated as {[Co 2 (μ 6 -L)(μ-obtx) 2 ]·2H 2 O} n (1) , [Co 2 (μ 6 -L)(μ-mbtx) 2 ] n (2) , [Zn 2 (μ 7 -L)(μ-btb) 0.5 ] n (3) , {[Zn 2 (μ 4 -L)(μ-obtx) 2 ]·2H 2 O} n (4) , {[Zn 2 (μ 4 -L)(μ-mbtx) 2 ]·2H 2 O} n (5) and {[Zn 4 (μ 4 -L) 2 (μ-pbtx) 4 ]·6H 2 O} n (6) [H 4 L: (E)-1,4-bis(3,5-dicarboxyphenoxy)but-2-en, btb: 1,4-bis(1 H -1,2,4-triazol-1-yl)butane, obtx: 1,2-bis((1H-1,2,4-triazol-1-yl)methyl)benzene, mbtx: 1,3-bis((1H-1,2,4-triazol-1-yl)methyl)benzene, pbtx: 1,4-bis((1H-1,2,4-triazol-1-yl)methyl)benzene] were synthesized and characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction techniques. To confirm the phase purity of the complexes, powder X-ray diffraction experiments were carried out. According to the results of single crystal X-ray diffraction analysis, 1 and 2 show a two-fold 3D + 3D → 3D interpenetrated frameworks with sqc27 topology while 3 exhibits 3D framework with the point symbol of (3.5.6) 4 (3 2 .5 4 .6 4 .8 2 .9 3 )(5 2 .6 2 .8 2 ). Complex 4 exhibits three-fold 3D + 3D + 3D → 3D interpenetrated framework and display bbf topology with the point symbol of (4.6 2 ) 2 (4 2 .6 10 .8 3 ). The complex 5 is a 4-connected 2D coordination polymer with the kgm topology (point symbol of 3 2 .6 2 .7 2 ), while 6 is two nodal 4,4-connected 3D framework with the point symbol of 8 6 . In addition, luminescence, topological, optical and thermal properties of the complexes were investigated.