Synthesis, Crystal Structure and Magnetic Properties of a Novel Gd^III -Cu^II Heterodinuclear Complex

Abstract

Heterodinuclear Complex, Super-Exchange Interactions, Lanthanides Preparation, crystal structure and magnetic properties of a heterodinuclear complex, LCu(Me2C0 )Gd(N03)3 (L = (N,N'-bis(3-methoxysalicylidene)propane-1,2-diamine) are re ported. The crystal structure of the complex was determined by X-ray diffraction methods at 200 K. (Ci9H22N20 4 )Cu(C3H6 0 )Gd(N0 3 )3, monoclinic, space group P2i/c, with a = 9.795(9), b = 18.763(3), c = 15.579(2) A , ß = 95.297(2) V = 2850.9(7) A3 and Z= 4. The central region of the complex is occupied by Cu(II) and Gd(III) ions which are bridged by two phenolato oxygen atoms of the ligand. The copper ion adopts a square-based 4+1 coordination mode, the equatorial N2O2 donors being afforded by the ligand while the axial position is occupied by an oxygen atom of the acetone molecule. The Gd(III) ion is deca-coordinated. In addition to the two phenolate oxygen atoms, the coordination sphere contains two oxygen atoms of the OMe side arms of L and six oxygen atoms from the three bidentate nitrate ions. The G d... Cu separation is 3.425(3) A and the dihedral angle between the GdO(l)Cu and GdO(2)Cu planes is 164.8°. The magnetic susceptibility of the complex was measured over the range 5 -350 K and the observed data were successfully simulated by the equation based on the spin-Hamiltonian operator (H = -/SorSGd), giving the exchange integral 7(Cu-Gd) = 5.6(1) cm-1. This indicates a weak ferromagnetic spin exchange interaction. The nature of the magnetic super-exchange interaction of the title compound is compared with similar [Gd(III)-Cu(II)] heterodinuclear complexes.

Host–guest chemistry of a chiral Schiff base copper(ii) complex: can chiral information be transferred to the guest cation?

“…[22][23][24] A detailed study by Cunningham and co-workers of reactions between Na + , K + and Cs + salts with Schiff base complexes [ML] (M ¼ Co, Ni, Cu, Zn; H 2 L ¼ 1,6-bis(2-hydroxy-3methoxyphenyl)-2,5-diazahexa-1,5-diene, 1,6-bis(2-hydroxy-3-methoxyphenyl)-3-methyl-2,5-diazahexa-1,5-diene and 1,7-bis(2hydroxy-3-methoxyphenyl)-2,6-diazahepta-1,6-diene showed a tendency for the sodium ion to reside in the plane of the O 4donor set whereas the larger group 1 metal ions were bound out of plane, generating simple or stacked sandwich structures. 12 Among the structurally characterized assemblies within the families so far reported, only a limited number incorporate Schiff base ligands with chiral backbones, 6,8,12,16,[18][19][20][25][26][27][28][29][30][31][32][33][34] and structural studies involving enantiopure ligands appear to be rare, 18,34 despite the wide application of chiral auxiliaries in Schiff-base complexes used in asymmetric catalysis. 35 We report here an investigation of the ability of [Cu{(R,R)-1}] to bind ammonium and s-block metal ions.…”

(Acetone-2κO){μ-6,6′-dimethoxy-2,2′-[propane-1,2-diylbis(nitrilomethylidyne)]diphenolato-κ81:2O6,O1,O1′,O6′:O1,N,N′,O1′}tris(nitrato-1κ2O,O′)copper(II)samarium(III)

“…The Cu II center is five-coordinate by two nitrogen atoms and two oxygen atoms from the ligand and one oxygen atom from acetone in a square-pyramidal geometry. The title compound is isostructural with the previous Cu-Ln complexes (Ln = Gd, Pr and Tb) (Kara et al, 2000;Sun et al, 2007Sun et al, , 2009 derived from the same ligand.…”

“…For similar Cu-Ln (Ln = Gd, Pr and Tb) dinuclear complexes of the N,N 0 -bis(3-methoxysalicylidene)propane-1,2-diamine ligand, see: Kara et al (2000); Sun et al (2007Sun et al ( , 2009.…”

One-dimensional salen-type heterospin trimetallic (3d–4f–3d′) chain-like coordination polymers: Syntheses, crystal structures and magnetic properties

“…1. The [LCuGd] moiety preserves the structural features of the whole [Cu(II)Ln(III)] family of complexes with compartmental salen-type ligands [7,8]. The Cu(II) ion is hosted in the inner N 2 O 2 compartment, and the oxophilic Gd(III) ion occupies the outer O 4 cavity.…”