Synthesis, characterization, single crystal structure and DFT calculations of [Cu(temed)(H2O)4](1,5-napthalenedisulphonate)⋅2H2O

A new cationic species [Cu(temed)(H2O)4]2+ has been isolated in the form of a complex 1, [Cu(temed)(H2O)4](1,5-napthalenedisulphonate)⋅2H2O (1) (where temed = N,N,N′,N′-tetramethylethylenediamine). The complex 1 was crystallized from a reaction of disodium salt of 1,5-naphthalenedisulphonic acid with equimolar quantity of CuCl2⋅2H2O and temed in methanol:water (4:1, v/v) mixture and characterized by elemental analyses, spectroscopic techniques (e.g. UV/Visible, IR) and conductivity measurements. Single crystal X-ray structure determination revealed the presence of discrete ions: one [Cu(temed)(H2O)4]2+ complex cation, one 1,5-napthalenedisulphonate anion and two water molecules of crystallization. The crystal lattice is stabilized by the extensive hydrogen bonding (OH⋯O and CH⋯O) between the cationic and anionic moieties resulting in a bi-layered structure, the new cationic species being caged in H-bonding network of anions. DFT calculations indicated a different geometry.