Design of high-spin organic molecules: toward magnetic parts in molecular electronics

High-spin organic molecules are currently attracting great interest not only from the scientific viewpoint per se but also as the candidate for magnetic parts in molecular electronics. In this context, we have prepared interesting molecules, spiro-fused bis(diphenylamine)s, 10,10′-spirobi[5,10-dihydrophenazasiline]s as the first step to obtain the novel di(nitroxide radical)s. These bis(diphenylamine)s showed two reversible one-electron redox couples by cyclic voltammetry, indicating that the two diphenylamine moieties are correlated each other through spiro-conjugation. Oxidation reaction of these amines resulted in mononitroxide species, the forbidden transitions in which were observed in the electron spin resonance spectra of its powder sample, showing S⩾3/2. This suggests that there exists a sort of intermolecular magnetic interaction in the solid state of the mononitroxide species.