Four new copper(II) complexes with di-substituted s-triazine-based ligands

In this paper, two di-substituted triazine-based ligands, 6-chloro-N,N,N′N′-tetrakis-pyridin-2-ylmethyl-[1,3,5]triazine-2,4-diamine (L1), and 6-chloro-N,N′-bis-pyridin-2-ylmethyl-N,N′-bis-thiophen-2-ylmethyl-[1,3,5]triazine-2,4-diamine (L2), have been prepared. Reaction of CuCl2·2H2O and Cu(NO3)2·3H2O with L1 and L2 results in the formation of [Cu2Cl4(L1)]·3MeOH (compound 1), [Cu4(NO3)8(L1)2]·2.07CH2Cl2·0.93MeOH (compound 2), [Cu2Cl4(L2)2] (compound 3) and [Cu(NO3)2(L2)]·CH2Cl2 (compound 4), respectively, which have been fully characterized and determined by single-crystal X-ray crystallography, FT-IR, elemental analysis, thermogravimetric measurement and magnetic susceptibility. The dinuclear compound 1 shows strong π–π interactions between the neighboring pyridine rings. The nitrate–π (1,3,5-triazine ring) interaction with the distance of 2.755Å in compound 2, is the closest contact reported so far. Compounds 3 and 4 are mononuclear copper(II) compounds, in which none of thiophene rings coordinates with copper(II) ion. In addition, the different orientations of two thiophene rings in compounds 3 and 4 lead to the π–π and CH2Cl2–π (thiophene ring) interactions in compound 4, but not in compound 3.