Template condensation reactions of 5-methylsalicylaldehyde with 4,5-dimethyl-1,2-phenylenediamine in the presence of copper(II) and selected lanthanide(III) ions

The one-step condensation reactions of 5-methylsalicylaldehyde with 4,5-dimethyl-1,2-phenylenediamine in the presence of Cu(II), Eu(III), Gd(III), Yb(III) ions led to obtain [Eu3L14(H2O)2](CF3SO3) and [CuL1] complexes with H2L1 ligand. Moreover, in these synthesises were obtained L2 and L3 ligands, and their triflate and nitrate salts, respectively. [Display omitted] This article presents the template condensation reactions of 5-methylsalicylaldehyde with 4,5-dimethyl-1,2-phenylenediamine in the presence of copper(II) ion and selected lanthanide(III) ions: Eu(III), Gd(III), and Yb(III). These reactions yielded complexes with a new salen-type Schiff base, namely N,Nʹ-bis(5-methylsalicylidene)-4,5-dimethyl-1,2-phenylenediamine (H2L1). The complexes of different compositions, [Eu3L14(H2O)2](CF3SO3) and [CuL1], were characterized by spectroscopic methods and elemental analysis. The reaction of 5-methylsalicylaldehyde with 4,5-dimethyl-1,2-phenylenediamine in the presence of Yb(NO3)3, Eu(CH3COO)3, and Yb(CF3SO3)3 also produced another ligand, L2 (2-(5,6-dimethyl-1H-benzimidazol-2-yl)-4-methylphenol and its triflate salt. The next template condensation reaction of the same organic reactants in the presence of Eu(NO3)3 and Gd(NO3)3 yielded a new ligand, L3 (2-[1-(2-hydroxy-5-methylbenzyl)-5,6-dimethyl-1H-benzimidazol-2-yl]-4-methylphenol and its nitrate salt. For the complexes [Eu3L14(H2O)2](CF3SO3) and [CuL1], the magnetic susceptibility χ(T) was measured under a magnetic field of µ0H = 0.5 T in the temperature range of 2–300 K.