Hydrothermal Synthesis, Structural Characterization, Magnetic and Photoelectric Properties of Two Cobalt(II) Coordination Polymers

Abstract

Two cobalt(II) coordination polymers, {[Co(µ-4,4Јbipy)(4,4Ј-bipy) 2 (H 2 O) 2 ]·(OH) 3 ·(Me 4 N)·4,4Ј-bipy·4H 2 O} n (1) and {[Co(µ-4,4Ј-bipy)(H 2 O) 4 ]·suc·4H 2 O} n (2) (4,4Ј-bipy ϭ 4,4Ј-bipyridine, suc ϭ succinate dianions), were hydrothermally synthesized and structurally characterized by X-ray diffraction analysis, UV-Vis-NIR, and ICP. The main structure feature common to the both polymers is presence of the infinite linear chains, [Co(µ-4,4Јbipy)(4,4Ј-bipy) 2 (H 2 O) 2 ] n (1) and [Co(µ-4,4Ј-bipy)(H 2 O) 4 ] n (2), respectively. In 1, the chains are further linked by the hydrogenbond and π-π stacking interaction, producing extended layer structure. The 4,4Ј-bipy molecules in 1 play three different roles. In 2,

Poly[[diaquabis(μ2-4,4′-bipyridyl)cobalt(II)] dinitrate tetrahydrate]

“…by two aqua ligands [Co-O1w = 2.074 (10) Å] and four pyridil groups from 4,4′-bpy ligands (Fig. 1), with a distance Co -N in the range of 2.1898 (13) -2.2306 (14) Å which is almost similar to that observed in { Jin et al (2006), these last act as a bidentate bridging ligands giving rise to a 2-D square grid sheet of (4,4) topology lying in the (101) plane. The basal coordinated 4,4′-bpy is located on an inversion center, it is planar with a 0° interplanar angle between the two pyridil rings, the same thing is observed in { Aoyagi et al (2000), whereas the axially one is nonplanar with an angle of 45.60° between the pyridil rings.…”

“…For related structures with 4,4 0 -bpy ligands, see: Aoyagi et al (2000); Felloni et al (2002); Jin et al (2006); Tong et al (2000).…”

A Molecular Antenna Coordination Polymer from Cadmium(II) and 4,4’-Bipyridine Featuring Three Distinct Polymer Strands in the Crystal

“…These include (4,4) square grid (Scheme 1(d)) [20][21][22][23][24] and 'T-shape' [20] 2D coordination networks, as well as linear chain (Scheme 1(a)) [19,20,25,26] and molecular antenna [19,21] 1D coordination polymers. The term molecular antenna commonly refers to a 1D coordination polymer with the underlying topology of the linear chain (Scheme 1(a)) bearing two additional, terminally monodentate-bound 4,4'-bipy ligands at each metal node [19,21,[27][28][29][30][31][32][33][34]. Historically, Robson and co-workers were the first to report (4,4) square grids with the composition [{Cd(μ-4,4'-bipy) 2 (1).…”

<b>Hydrothermal synthesis and characterization of a binuclear complex and a coordination polymer of copper(II)</b>

“…This method with an aqueous solvent as a reaction medium is environmentally friendly since the reactions are carried out in a closed system [2,3]. Hydrothermal synthesis has been successful for the preparation of some solids such as microporous crystals [4], super ionic conductors [5], chemical sensors [6], complex oxide ceramics and fluorides [7,8], materials including nanometer particles [2,9] and transition metal complexes [10][11][12][13]. The molecular structures of complexes obtained by this method are unexpected compared to those obtained by the common solution methods [13,14].…”