Complementarity and countercomplementarity in polynuclear copper(ii) complexes with R2NCH2CH(OH)CH2NR2 (R = H, CH3): crystal structures and magnetic study

Abstract

The syntheses, structural characterization and magnetic behavior of five new copper(II) polynuclear compounds with formulae [Cu₄(μ₂-CH₃COO)₂(μ-bdmap)₂(μ_1,5-dca)₂(dca)₂(H₂O)₂] 1, [Cu₂(μ₂-CH₃COO)(μ-bdap)(μ_1,1,5-dca)(μ_1,3-dca)]_n2, [Cu₄(μ₂-CH₃COO)₂(μ-bdmap)₂(μ_1,1-NCS)₂(NCS)₂] 3, [Cu₂(μ₂-CH₃COO)(μ-bdap)(NCS)₂] 4 and [Cu₂(μ_1,3-N₃)(μ-bdmap)(N₃)₂]_n5 in which bdmapH is 1,3-bis(dimethylamino)-2-propanol, bdapH is 1,3-bis(amino)-2-propanol and dca is the anionic dicyanamide ligand, are reported herein. Tetranuclear complex 1 crystallizes in the monoclinic system, space group P2₁/n, with unit cell parameters a = 8.284(8), b = 21.52(1), c = 11.432(3) Å, β = 105.19(2)°, Z = 2. Bi-dimensional complex 2 crystallizes in the triclinic system, space group P, with unit cell parameters a = 8.184(5), b = 8.792(2), c = 10.887(2) Å, α = 75.65(2), β = 76.55(3), γ = 74.36(3)°, Z = 2. Tetranuclear complex 3 crystallizes in the triclinic system, space group P, with unit cell parameters a = 8.455(4), b = 9.114(9), c = 12.744(8) Å, α = 104.62(8), β = 99.86(6), γ = 106.10(8)°, Z = 1. Dinuclear complex 4 crystallizes in the triclinic system, space group P, with unit cell parameters a = 8.15(1), b = 8.18(2), c = 11.44(1) Å, α = 69.39(2), β = 80.36(2), γ = 80.37(2)°, Z = 2. One-dimensional complex 5 crystallizes in the orthorhombic system, space group P2₁2₁2₁, with unit cell parameters a = 20.45(4), b = 11.36(3), c = 6.43(1) Å, Z = 4. The magnetic behavior of all the complexes has been checked giving a bulk antiferromagnetic coupling in all the cases with |J| values in the range 109–144 cm⁻¹ for 1–4. Compound 5 is diamagnetic in the 2–300 K range of temperatures. The found J values for 1–5 can be justified from the structural data taking into account the orbital countercomplementarity for 1–4 and the orbital complementarity for 5.