Synthesis and characterization of some transition metal complexes with mixed adenine and acetylacetonate ligands

Abstract

Metal complexes of divalent copper (1–2), cobalt (3), and nickel (4) with mixed ligands acetylacetone (acac) and adenine were prepared and characterized by IR, mass spectra, elemental and thermal analysis. The X-ray crystal structures of {[Cu(acac)2(adenine)]·EtOH} complex (1) and {[Cu(acac)2(adenine)]·DMF·H2O} (2) were determined. Compound (1) crystallizes in the triclinic space group P − 1 with a = 7.547(3) Å, b = 7.828(3) Å, c = 17.791(6) Å, α = 79.538(6)°, β = 82.240(7)°, γ = 86.010(6)°, V = 1023.1(6) Å3, and Z = 2. Complex (1) forms a hydrogen bonded 2:2 complex {[Cu(acac)2(adenine)]2:[EtOH]2} arranged in bilayers. Complex (2) crystallizes in the triclinic space group P − 1 with a = 7.828(2) Å, b = 8.095(2) Å, c = 16.995(5) Å, α = 78.508(5)°, β = 84.949(5)°, γ = 89.285(5)°, V = 1051.2(5) Å3, and Z = 2. Complex (2) also forms bilayers with H-bonded DMF. Thermal analysis TG and DSC of the compounds (25–800 °C, under N2) reveals the disproportionation of ligands with the associated heat.