Crystal structures of bis-{N-[1-(pyridin-2-yl-κN)ethylidene]nicotine hydrazide-κ2N’,O}cobalt(II)bis(perchlorate) dihydrate and bis-{N'-[1-(pyridin-2-yl-κN)ethylidene]nicotinohydrazide-κ2N',O}copper(II) perchlorate

Abstract

Complexes of Co(II), [Co(C₂₆H₂₄N₈O₂)]·(ClO₄)₂·(H₂O)₂ (1), and Cu(II), [Cu(C₂₆H₂₃N₈O₂)]·(ClO₄) (2), have been synthesized. The prepared two compounds were characterized by elemental analysis, infrared and their structures were determined by single-crystal X-ray diffraction. The compound 1 crystallizes in the triclinic space group P-1 with the following unit cell parameters: a = 8.880 (5) Å, b = 10.529 (5) Å, c = 18.430 (5) Å, α = 99.407 (5)°, β = 102.174 (5)°, γ = 100.652 (5)°, V = 1618.2 (13) ų, Z = 2, T = 293(2), μ(MoKα) = 0.77 mm^-1, Dcalc = 1.582 g/cm³, 16135 reflections measured (5.050° ≤ 2q ≤ 59.152°), 7648 unique, R_int = 0.034 which were used in all calculations. The final R₁ was 0.066 (I ≥ 2σ(I)) and wR₂ was 0.22 (all data). The compound 2 crystallizes in the monoclinic space group P2₁/c with the following unit cell parameters : a = 11.652 (5) Å, b = 16.540 (5) Å, c = 14.512 (5) Å, β = 93.495 (5)°, V = 2791.6 (18) ų, Z = 4, T = 293(2), μ(MoKα) = 1.05 mm^-1, Dcalc = 1.768 g/cm³, 15592 reflections measured (5.624° ≤ 2θ ≤ 58.804°), 6630 unique, R_int = 0.025 which were used in all calculations. The final R₁ was 0.050 (I ≥ 2σ(I)) and wR₂ was 0.144 (all data). In both complexes, the ligand acts in a tridentate fashion. In the structure of the mononuclear complex 1, the Co(II) cation is coordinated by two ligand molecules. The basal plane around the Co(II) cation is occupied by two pyridine nitrogen atoms and two carbonyl oxygen atoms. Two imino nitrogen atoms occupy the apical positions of the distorted square-pyramidal geometry. The mononuclear 2 consists of a Cu(II) coordinated by one ligand and one monodeprotonated ligand molecule. The metal center lies in a distorted square bipyramidal environment. The basal plane around the Cu(II) is occupied by two pyridine nitrogen atoms and two carbonyl oxygen atoms, the apical position being occupied by the two imino nitrogen atoms.