Synthesis and applications of lanthanoid complexes of pentadentate and hexadentate N5 and N6 macrocycles: A review

In this paper, the lanthanoid complexes of N5 and N6 macrocycle ligands, without pendant arms or additional heteroatoms, are surveyed. This review covers the period from 2015 to the current date, since in 2014 Schiff base macrocyclic ligands incorporating the pyridine moiety, and their complexes, were revised, and in 2015 the chemistry of pentaaza macrocycle ligands with rare earth metals was also summarized. Porphyrin and phthalocyanine ligands are not included in this review, which primarily focuses on complexes with Schiff bases and amines without pendant arms or any additional donor other than nitrogen. The synthetic methods, structural characterization, based on single X-ray crystal data, and properties of the lanthanoid complexes, with special attention to magneto-structural correlations, are presented herein.