Strong Ferromagnetic Exchange Couplings in Copper(II) and Nickel(II) Complexes with a Paramagnetic Tridentate Chelate Ligand,2,2'-Bipyridin-6-yl tert-Butyl Nitroxide

摘要

Metal-radical hybrid solids have been well investigated toward molecule-based magnets.Various 2-pyridyl-substituted ligands containing paramagnetic nitronyl nitroxide (NN),imino nitroxide (IN),oxoverdazyl (VD),and dithiadiazolyl (DTDA) groups have been known to form chelate rings where a radical center is directly bonded to the metal ion (Chart 1).Herein we propose 2-azaaromatic tert-butyl nitroxide (ArNO; NO stands for the tert-butyl nitroxide group) radicals as a paramagnetic chelating ligand,but such reports have been missing in the literature.