Chiroptical properties and magnetism of chiral and achiral phenyl α-nitronyl nitroxides in the solid state

We have measured the solid state circular dichroism of a new family of phenyl α-nitronyl nitroxides, which contain a chiral group linked to the phenyl ring, and also of an achiral one, which crystallizes in a non-centrosymmetric space group, and discuss correlation of the spectra with the crystal structure geometries of the compounds. The Cotton effects are attributed to the ONCNO chromophore (the radical unit), and transmission of chirality from the stereogenic center to this unit as well as the magnetic properties they present are very important in regard to the prospects of measuring magneto-optical effects in these compounds, and other related ones.