Several phenoxy radicals were chemically modified in order to probe the intermolecular spin interactions between these radicals. Based on the ketenimine chemistry, we demonstrated an efficient synthetic sequence for the preparation of new dicyano substituted hindered phenols. A series of new polar group substituted nitroxide-nitroxyl radicals were also synthesized. These radicals with polar functionalities include 3, 5-dinitro-phenyl, 3, 5-dimethoxyphenyl, 3, 5-dihydroxyphenyl, 4-hydroxyphenyl, 4-cyanophenyl, 3, 5-dicyano-phenyl, and 3, 5-di-i-butyl-4-hydroxyphenyl derivatives of 4, 4, 5, 5-tetramethylimidazolidine-3-oxide-1-oxyl. They are intended for the study of functional substitution effects on the nature of spin exchanges in solid state.