Production of stable nitroxide radicals of 3-imidazoline-3-oxide

1. The condensation of α-hydroxylaminooximes with the hydroxylamino group at a tertiary carbon atom with the diethylketal of acetone leads to 1-hydroxy-2,2,5,5-tetrasubstituted-3-imidazoline-3-oxides. The use of acetates of α-hydroxylaminooximes in a number of cases permits an appreciable increase in the yields of the condensation products. 2. The possibility of exchange of the protons of the α-methyl and α-methylene groups of the ketonitrone groups of 3-imidazoline-3-oxides for deuterium was detected. 3. Stable nitroxides were produced by oxidation of 1-hydroxy-2,2,5,5-tetrasubstituted-3-imidazoline-3-oxides with lead dioxide.