A diversity of hydrogen bond motifs in the crystal structures of nickel(II) and copper(II) complexes with N-arylalkyliminodiacetamides

The reactions of N-arylalkyl derivatives of iminodiacetamide (Bnimda, Peimda, Ppimda; Bn = benzyl, Pe = 2-phenylethyl; Pp = 3-phenylprop-1-yl) with nickel(II) and copper(II) salts in aqueous solutions were investigated. Four new nickel(II) complexes and three new copper(II) complexes [Ni(Bnimda)2](NO3)2·2H2O (1), [Ni(Peimda)2](NO3)2 (2), [Ni(Peimda)2]SO4·2H2O (3), [Ni(Ppimda)2](NO3)2·4H2O (4), [Cu(Bnimda)2](NO3)2·H2O (5), [Cu(Peimda)2](NO3)2·4H2O (6) and [Cu(Ppimda)2](NO3)2 (7) were prepared and characterized by infrared spectroscopy and thermal analysis (TG/DTA). The distorted octahedral coordination environments around the nickel(II) and copper(II) ions in complexes 1, 2, 3, 5 and 6 consist of two O,N,O′-tridentate N-arylalkyliminodiacetamide ligands, with imino N atoms in trans-position. Various hydrogen bond motifs were found in the crystal structures of these complexes – trimeric, tetrameric, pentameric and hexameric ring motifs. These motifs were formed by the amide moieties and by the oxoanions (nitrate or sulfate) and water molecules.

Graphical abstractNickel(II) and copper(II) complexes with iminodiacetamide derivatives (Rimda), namely Bnimda, Peimda and Ppimda (Bn = benzyl; Pe = 2-phenylethyl; Pp = 3-phenylprop-1-yl) were prepared and characterized by IR spectroscopy and thermal analysis (TG/DTA). The X-ray structural analysis revealed distorted octahedral coordination of nickel(II) and copper(II) ions in all studied complexes.Figure optionsDownload full-size imageDownload as PowerPoint slide