Novel trifluoromethyl-containing imidazo-1,4-oxazines have been synthesized through the condensation reaction of 4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-one with 2-aminoethanol (2-AE) and 2-aminophenol (2-APh). Unusual route of the reaction of 1-methyl(phenyl)- 4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-ones with 2-AE has been found, leading to hydroxyethylamino-substituted hydantoins. The interaction of the N-substituted imidazolidines with 2-APh under similar conditions led to formation of rearrangement products, 5,5-bis(trifluoromethyl)hydantoins. The molecular structure of 5-[(2-hydroxyethyl)amino]-3-methyl-5-(trifluoromethyl)imidazolidin-2,4-dione has been studied by X-ray diffraction experiment.