New spirocyclic nitroxides of 2,5-dihydroimidazole series flanked by two mesogenic fragments

Abstract

N/C-Hydroxylated spirofused derivatives of 2,5-dihydroimidazole which were synthesized by condensation of 4-(4-hydroxyphenyl)cyclohexanone with aryl hydroxylaminoalkyl ketones in the presence of ammonia were determined to be trans-ee-isomers of 1,4-cyclohexane framework by NMR spectroscopy. Oxidation of the cyclic hydroxylamino moiety followed by acylation of the phenolic hydroxyl group with 4-alkyloxybenzoic acid chlorides led to the corresponding spirocyclic nitroxides bearing two mesogenic fragments.