Preparation and Characterization of a Tetraaza[14]Annulene Copper(II) Complex Having a Strapped Pyridine Group

The treatment of tetraaza[14]annulene or its copper(II) complex with 3, 3′-(2, 6-pyridyldimethyleneoxy)dibenzoylchloride hydrochloride gave the corresponding ligand or copper(II) complex with a strapped pyridine group. The mass spectra revealed the existence of the parent ions. The infrared spectra indicated strong C=O stretching frequencies in the range of 1640–1660 cm1. The general feature of electronic spectra for the strapped copper(II) complex is similar to that for the unstrapped copper(II) complex. The spin Hamiltonian parameters for the strapped and unstrapped copper(II) complexes are very analogous to each other. Consequently, it is found that the strapped copper(II) complex hardly possesses a distortion in the macrocyclic ring with the substitution of the strapped pyridine group.