Effect of 4-position pyridine ring substitution on Zn(II) complexes of 4-substituted Py₂N₂ pyridinophane macrocycles

The metal binding properties of macrocyclic small molecules are a key property that drives the applications for which these ligands can be used. Pyridine-modified Py₂N₂ pyridinophane small molecules are a new class of macrocyclic small molecules, whose properties have not been explored. As a result, Zn(II) metal binding of a library of six pyridine-modified Py₂N₂ complexes is reported here. These results include ¹H NMR, log <i>β</i>_Zn(II), and X-ray diffraction, which are compared to PyN₃ congeners to show that the differences in each scaffold yield markedly different metal binding properties that can be exploited in future applications.