Synthesis, structural, EPR and magnetic analysis of nitronyl-nitroxide labelled isophthalic acid

Article abstract of DOI:10.1016/S0040-4039(99)00330-5

The high yield synthesis of an isophthalic acid derivative bearing a nitronyl-nitroxide moiety at the 5-position was achieved. The structural analysis in the crystalline phase by X-ray diffraction on single crystals revealed the formation of a 3-D network through strong H-bonds between the acid groups and the nitronyl-nitroxide moieties. The spin label obtained was also analysed by EPR spectroscopy which showed a five line pattern with a(N)=7.51 G and a g-factor of 2.0066. Magnetic measurements revealed that at low temperature, the systeme showed a Curie-Weiss like behaviour with weak ferromagnetic intermolecular interactions.