New bis-nitronyl nitroxide and iminyl nitroxide molecules for studies on molecular magnetism

New bis-nitronyl nitroxide and iminyl nitroxide molecules 1, 2 and 3 were synthesized and characterized by IR, FAB-MS, ESR and EA. Crystal structures of 1 and 3 were determined by X-ray diffraction analysis. Magnetic studies indicated that all of them showed antiferromagnetic properties in solid state, but with strong intermolecular spin-spin coupling as indicated by the relatively large values of θ, in particular for 1. Possible spin-spin interaction mechanism was suggested based on the crystal structures of 1 and 3.