MANIFESTATION OF INTRAMOLECULAR AND INTERMOLECULAR INTERACTIONS IN INFRARED ABSORPTION SPECTRA OF BIOLOGICALLY ACTIVE AMINOPHENOLS

FTIR methods were used to study intramolecular and intermolecular interactions in solutions and the solid state of the biologically active aminophenols 2-anilino-4,6-di-tert-butylphenol, N-(3,5-di-tert-butyl-2-methoxyphenyl) aniline, and 2,4-di-tert-butyl-10H-1-phenothiazinol. An analysis of the IR spectra has shown that intramolecular interactions between the OH and NH groups occur in solutions of 2-anilino-4,6-di-tert-butylphenol in CCl4 to form O-H center dot center dot center dot N hydrogen bonds. The NH groups in solutions of N-(3,5-di-tert-butyl-2-methoxyphenyl) aniline in CCl4 are present in the non-associated state because of the absence of hydroxyl groups in the molecular structure. The OH and NH groups in solutions of 2,4-di-tert-butyl-10H-1-phenothiazinol in CCl4 do not interact within the molecule due to a decrease in the conformational mobility of the molecular fragments due to the presence of the rigid C-Ar-S-C-Ar molecular bond in this compound. Intermolecular interactions involving the NH groups occur in the solid state of these compounds.