Construction of Planar Clusters Using Planar Aromatic Polyoxime Ligands: Synthesis, Structure, and Magnetic Properties

Abstract

The reactions of NiSO4·6H2O or Mn(CH3COO)2·4H2O with the planar ligands of indane-1,2,3-trione trioxime (H3Itto) or indane-1,2,3-trione-1,2-dioxime (H2Itdo) gave two planar pentanuclear clusters [Et3NH]2[Ni5(HItto)4(MeOH)2(H2O)6(SO4)2]·2H2O (1) and [Ni5(HItdo)2(Itdo)2(DMF)4(MeOH)(H2O)(SO4)2]·CH3OH·6H2O (2), one planar trinuclear cluster, [MnIII 3(μ3-O)(Itdo)3(CH3COO)(DMF)2(H2O)2]·H2O (3), and one planar platelike trinuclear cluster, [MnIII 3(μ3-O)(Itdo)3(CH3COO)(DMF)2(MeOH)(H2O)]·H2O (4). Five Ni(II) ions of 1 and 2 are consolidated by four indane-1,2,3-trione trioxime ligands and four indane-1,2,3-trione-1,2-dioxime ligands, respectively, to form square topological planar pentanuclear clusters with five Ni(II) ions and all atoms of the four oxime ligands nearly in one plane. However, 1 and 2 show some differences in the bridging of the central metal ion with the metal ions on the square corners. Both 3 and 4 feature a planar isosceles triangular [Mn3(μ3-O)]7+ core. Each edge of the triangular [Mn3(μ3-O)]7+ core in 3 and 4 is bridged by a μ2,η3-bridging indane-1,2,3-trione-1,2-dioxime ligand to construct a planar skeleton for 3 with the central oxygen atom, three Mn(III) ions, and all atoms of the indane-1,2,3-trione-1,2-dioxime ligands nearly in one plane, and a planar platelike skeleton for 4 with the ligand planes deviating from the triangular metal plane. Magnetic studies of 1−4 reveal the presence of antiferromagnetic interactions between the metal ions in 1−4.

Enforcement of a high-spin ground state for the first 3d heterometallic 12-metallacrown-4 complex

“…So far, however, the 12-MC-4 complexes have remained of limited application within the community as they in general lack a high-spin ground state. [9][10][11][12][13][14] This also holds true for Mn(II)(OAc) 2 N(Shi) -4](DMF) 6 , which has been identified as a SMM. 15 Here, the lowspin ground state is compensated by the single-ion anisotropy contributions due to the beneficial planar structure of metallacrowns.…”

“…Because the antiferromagnetic radial magnetic interactions are of similar strength to the tangential exchange couplings, a near-complete cancellation of the spins is observed in these systems. 9,10 Herein, we present the first results of a complementary heterometallic approach for metallacrowns. The purposeful placement of specific transition metal ions in the different sites of the metallacrown targets a more distinct differentiation of the coupling strengths.…”

Crystal structure of μ-oxo-di-μ-sulfato-κ2O:O′-bis[(2,2′-bipyridine-κ2N,N′)-bis(dimethylsulfoxide-κO)-diiron(III)]monohydrate, C24H30Fe2N4O12S4

“…There areseveral examples of zero dimensional discrete metal sulfates [10][11][12][13][14][15][16][17][18][19].E arlier Xu et 4 ]·6H 2 Ou sing 4,4'-bipyridine (4,4'-bpy)a s the directing ligand under hydrothermal conditions [19].In2006, Zhao et.al.,synthesized aFe(III) sulfate dimer containing 1,10-phenanthroline as ligand [20]. Recently, Brechin et.al.,reported a couple of hexanuclear iron(III)cage compounds [21][22].…”

Polynuclear ampyrone based 3d coordination clusters

“…The MS (positive-ion mode) for 1 shows two main peaks at the regions of 671. 19 44 Further topological analysis of these compounds using TOPOS software 58 and implementing monoatomic bridges to connect the metal centres 59 yields the following eight motifs shown in Figure 7; two twisted triangles sharing one edge (2,4M5-1) 60,61 linear (1,2,2M5-1) 62,63 , cross-like (1,4M5-1) 64,65 , trigonal bipyramidal-like (2,3M5-1, 66 2,3,3M5-1 67 and 3,4M5-1 68 ), ring-like (2M5-1) 69,70 and pentagonal like (4M5-1) 71 . The topological analysis of compound 8 gives an NDk-m symbol 2,3,4M5-1 and this is the first example ever seen in Ni chemistry.…”