Molecular and crystal structures of three 2,2,6,6-tetramethylpiperidine derivatives, including two stable radicals are determined for the first time. The XRD data obtained for two other stable TEMPO radicals are refined. A stable peroxosolvate of the nitroxide radical is reported. The corresponding intermolecular hydrogen bonds are determined for all compounds containing acidic protons.
Medvedko et al. (Sun,) studied this question.