Probing the Coordination Chemistry of N-2-Pyridylimidoyl-2-pyridylamidine: A Versatile Ligand with Multiple Coordination Sites

The research presented herein focuses on controlling the coordination environment of Mn, Fe, and Co in coordination complexes with the ligand N-2-pyridylimidoyl-2-pyridylamidine (Py2ImAm), which possesses both a bidentate and tridentate coordinating site. The synthesis and characterization of seven new metallic complexes are described, and these results indicate that the key factor dictating which coordination site of Py2ImAm the metal ion prefers is the presence (or absence) of a weak acid. More specifically, the presence of a weak acid directs the metal ion to the tridentate site of Py2ImAm, while neutral or basic conditions lead to coordination complexes in which the metal center is bound to the bidentate pocket.