Cobalt and Copper Coordination Polymers Containing Acetylacetonato‐Derived Ligands and Bidentate Pyridine Coligands: Synthesis, Crystal Structures and Magnetic Properties

Abstract

Keywords: Chain structures / X-ray diffraction / Magnetic properties / N ligands / O ligandsOne-dimensional chain derivatives of the general formula [M(acac) 2 (µ-bipyridine)] were obtained from (acetylacetonato)cobalt(II) or (trifluoromethylacetylacetonato)copper(II) derivatives and bipyridine-like bridging ligands: 1,2-bis(4-pyridyl)ethane, 4,4Ј-bpa (1, Co; 2, Cu), trans-1,2-bis(4-pyridyl)ethylene, 4,4Ј-bpe (3, Co; 4, Cu), 1,2-bis(2-pyridyl)ethylene, 2,2Ј-bpe (5, Co) or pyrazine (7, Cu). The reaction of the copper parent derivative with 2,2Ј-bpe gives rise, however, to a dimeric species [{Cu(tfacac) 2 } 2 (µ-2,2Ј-bpe)] (6). Derivatives 4-7 were characterized by X-ray crystallography, which showed linear (4, 7) or zigzag chains (5), depending on the bipyridine ligand shape. In the chain complexes, the metal centre is six-coordinate; the oxygen donor atoms of the ace-

Different coordination modes and supramolecular aggregations in copper(II) pentane-2,4-dionato compounds with 2-pyridone and 3-hydroxypyridine

“…In comparison, medium-to-weak interactions exhibit rather long centroid-centroid distances ( [75] and (4-cyanopyridine)-cis-bis(1,1,1-trifluoropentane-2,4-dionato)copper(II) [10] with centroid-centroid contacts between two parallel metallacycles of 3.16 and 3.24 Å and with CuÁÁÁCc distances of 3.33 and 3.26 Å , respectively, and in Cu(acac) 2 (adenine) ethanol solvate with centroid-centroid contact of 3.23 Å with the angle between metallacycles 0.02°and CuÁÁÁCc distance of 3.23 Å [44]. Centroid-centroid distances in the range from 3.27 to 3.49 Å with parallel metallacycles or deviating from planarity by up to 0.03°and with CuÁÁÁCc distances in the range from 3.30 to 3.46 Å were observed in several examples [11,42,44,45,[76][77][78][79][80].…”

(Pentane-2,4-dionato-κ2O,O′)(pyridin-2-amine-κN1)copper(II) and (pentane-2,4-dionato-κ2O,O′)(pyrimidin-2-amine-κN1)copper(II)

“…, with centroid-centroid contacts between two parallel metallacycles of 3.16 Å (Angelova et al, 1989). Centroid-centroid distances in the range 3.23-3.49 Å with parallel metallacycles (or deviating from planarity by up to 0.03 ) were observed in several examples (Lee et al, 2001;Zaworotko et al, 2009;Delgado et al, 2007;Jose et al, 1969;Stabnikov et al, 2008;Caneschi et al, 1988;Song & Iyoda, 2009;Judaš & Kaitner, 2006b;Yoshida et al, 2008;Atienza et al, 2008). Interestingly, when searching for centroid-centroid distances in the range 3.50-4.00 Å , as observed in compounds (I) and (II), we found only two structures, viz.…”

CuIIand ZnIIβ-diketonate coordination polymers based on pyrimidin-2-amine, pyrazine and 1,2-bis(4-pyridyl)ethane

“…Supramolecular structure is stabilized by weak C-HÁ Á Á interactions connecting phenyl rings with pyridyl rings of adjacent chains (Table S1) and by medium-tostrong Á Á Á interactions connecting phenyl rings of adjacent polymeric chains with centroid-to-centroid distances of 3.8925 (17) Å (Table S2). Analogously to pyz, bpet is also typically a bridging ligand and thus often used for the construction of polymeric materials (Tang et al, 2015;Atienza et al, 2008;Li et al, 2002). It is interesting that the benzoylacetonato ligand (bzac), a closely related non-fluorous analogue of tfpb, forms a monohydrate compound with copper ions, [Cu(bzac) 2 (bpet)]ÁH 2 O, which crystallizes in the orthorhombic space group (Li et al, 2005).…”