A tetrahedral zinc(II) complex of tris(2-pyridylethyl)amine.

The zinc ion in the title complex, [N,N'-bis(2-pyridylethyl)-2-(2-pyridyl)ethylamine-kappa 4N]zinc(II) diperchlorate, [Zn(C21H24N4)](ClO4)2, displays a distorted tetrahedral configuration. The Zn-Npy distances range from 1.979 (5) to 1.999 (5) A, while the Zn-Namine distance is 2.028 (5) A. The Npy-Zn-Npy and Npy-Zn-Namine angles range from 111.9 (2) to 119.6 (2) degrees and from 102.3 (2) to 103.4 (2) degrees, respectively. This behavior contrasts with the five-coordinate geometry normally observed in tripodal ligands of similar structure, and can be ascribed to the presence of weakly-coordinating anions and the ligand-metal chelate-ring size.