New <i>N</i>,<i>N</i>,<i>N</i>-Heteroscorpionates Based on 2,2‘-Bis(pyrazolyl)ethanamine and Its Derivatives. Ligands Designed for Probing Supramolecular Interactions

The successful design and synthesis of the new bis(pyrazolyl)ethanamine ligand and its copper(I) triphenylphosphine complex is reported. The ligand coordinates to the copper(I) center in a fac tridentate fashion, through both the pyrazolyl rings and the nitrogen atom from the NH2 group. In the solid state, the compound is organized in a 2D noncovalent network by N−H···π and C−H···π interactions and hydrogen bonds. The analogous ligand with a benzyl group substituted on the amine forms a complex with the same copper(I) center that has a similar 2D supramolecular structure and, in addition, is organized by the benzyl synthon into a 3D architecture.