One-Pot Synthesis, Crystal Structures and Thermal Properties of Two Three-Dimensional Cobalt(II) Complexes

Abstract

Two cobalt(II) compounds [Co(2,2'-bipy)(H 2 O) 2 (SO 4 )] n (1) and [Co 2 (2,2'-bipy) 2 (btec)(H 2 O) 6 ]·2H 2 O (2) (2,2'-bipy = 2,2'-bipyridine, H 4 btec = 1,2,4,5-benzenetetracarboxylic acid), have been simultaneously synthesized by a one-pot slow solvent evaporation reaction. Their structures were determined by single-crystal X-ray diffraction and further characterized by X-ray powder diffraction (XRPD), IR, elemental and thermogravimetric analysis (TGA). The structural analysis reveals that compound 1 exhibits an infinite 1D chain structure with the octahedral Co(II) centers bridging by the tetrahedral µ 2 -SO 4 2− ligands, while compound 2 possesses a dinuclear Co 2 (2,2'-bipy) 2 (btec)(H 2 O) 6 unit and the two adjacent octahedral Co(II) ions are linked by the bismonodentately coordinated btec ligand. Additionally, compound 2 exhibits blue fluorescent emission in the solid state at room temperature.

Hydrothermal synthesis and crystal structure of a new coordination polymer: [Zn1(deta)(btec)(H2O)2]n

“…This shows that the four oxygen atoms of the carboxylate group have monodendate connectivity (Fig.2) The monodendate connectivity of the btec acid has not been observed frequently. Similar monodendate connectivity of the btec acid has been observed before in the literature [29][30][31][32][33][34] . The present compound adds another example to this family of compounds.…”

Synthesis, crystal structures, luminescence and catalytic properties of two d10 metal coordination polymers constructed from mixed ligands

“…The absorption peaks at 1565 cm À1 and 1481 cm À1 for 1, and 1614 cm À1 and 1424 cm À1 for 2 may be attributed to the asymmetric and symmetric vibrations of carboxylate groups. In complex 2, all of the carboxylate groups are uncoordinated, but Dt[t as (COO) À t s (COO)] is 84 cm À1 for complex 1, indicating bidentate coordination of the carboxylate group to the metal center, which is consistent with X-ray structural analysis [29]. Characteristic bands at 1512 cm À1 for 1 and 1514 cm À1 for 2 are assigned to the m C@N stretching vibration of the benzimidazole rings.…”

Assembly and Catalytic Properties of a 3D (4,6)-connected Cobalt-organic Framework with fsh Topology

“…29 The strong bands at around 1571 cm 1 can be attributed to the  (C=N) absorption of the benzimidazole rings. The weak absorption peaks of -CH 2 -groups in the complexes appear at around 2985 cm…”