Unique 3d–4f Heterometallic Networks Based on a Nitronyl Nitroxide Radical Functionalized with Additional N and O Donors

Three 2D heterospin radical-3d–4f networks with the formula {[Ln(hfac)₃]₂[M(hfac)₂](NIT-3Py-5-Pyoe)₂}_n (M^II = Co^II and Ln^III = Gd 1, Dy 2; M^II = Cu^II and Ln^III = Dy 3; NIT-3Py-5-Pyoe = (2-(5-(4-pyridinone)-3-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)) have been successfully constructed using a novel multidentate nitronyl nitroxide paramagnetic ligand containing mixed N- and O-donor sites. In these 2D structures, the paramagnetic ligand acts as a tridentate linker to bind two Ln^III ions by means of one aminoxyl group and one pyridinone unit and one M^II ion through the pyridine ring. The magnetic behaviors of 1–3 are governed by predominant ferromagnetic radical–Ln interactions.