Crystal structure of trans-bis[2-(1H-benzotriazol-1-yl)acetato-κO]bis(ethanolamine-κ2N,O)copper(II)

Abstract

The reaction of 2-(1H-benzotriazol-1-yl)acetic acid (HBTA; C8H7N3O2) and monoethanolamine (MEA; C2H7NO) with CuCl2·2H2O resulted in the formation of the title complex, [Cu(C8H6N3O2)2(C2H7NO)2] or [Cu(BTA)2(MEA)2]. Its asymmetric unit comprises one BTA anion coordinating to the Cu2+ cation (site symmetry \overline{1}) through the carboxyl O atom, and one MEA ligand chelating the metal cation by two heteroatoms (O and N). The equatorial Cu—O and Cu—N bond lengths are similar at 2.029 (1) and 1.980 (2) Å, respectively, while the length of the axial Cu—O bond is considerably greater [2.492 (2) Å], as is typical for Jahn–Teller-distorted systems. An intramolecular hydrogen bond is present between the hydroxy group of the MEA ligand and the non-coordinating O atom of the carboxylate group. Intermolecular hydrogen bonding involving the amino function of the MEA ligand and the carboxylate group results in eight-membered rings with an R22(8) graph-set motif. The molecules are further linked by C—H...π interactions involving the triazole rings and methylene groups of MEA, thus generating an overall three-dimensional supramolecular framework.

Keywords

• copper(II)
• crystal structure
• benzotriazol
• monoethanolamine
• hydrogen bonding