The crystal and molecular structures of N,N′-di(2-acetylcyclohexenyl)ethylenediamine and its copper(II) complex

Abstract

The crystal structures of N,N′-di(2-acetylcyclohexenyl)ethylenediamine (L1) and its copper(II) complex, which crystallizes with one solvent molecule of chloroform (Cu(L1-2H)•CHCl3), were determined. Crystallographic details are as follows: L1 is monoclinic, space group P21/c, with a = 8.280(2), b = 11.692(2), and c = 9.355(2) Å, β = 114.10(2)°, V = 826.7(3) Å3, Z = 2; ρc = 1.22 g cm−3, μ(Cu Kα) = 5.93 cm−1, with the final residual indices of R = 0.046 and Rw = 0.070 for 991 unique reflections. Cu(L1-2H)•CHCl3 is triclinic, space group[Formula: see text] with a = 11.121(3), b = 11.713(3), and c = 8.974(2) Å, α = 99.35(2)°, β = 110.83(2)°, γ = 82.33(2)°, V = 1074(1) Å3, Z = 2; ρc = 1.50 g cm−3, μ(Cu Kα) = 50.74 cm−1, with the final residual indices of R = 0.048 and Rw = 0.077 for 2369 unique reflections. The X-ray diffraction study shows that in the crystal state the ligand L1 is in the methylketonecyclohexanonenamine isomeric form. For the copper complex Cu(L1 2H)•CHC13, the geometry around the metal atom is distorted square planar, and the angle between the chelate ring planes in the complex is 15.1°. An NMR study shows that L1 in solution has the same structure as that observed in the solid state by X-ray diffraction.