Studies in the relationship between molecular structure and chromatographic behaviour : IX. An assessment of the role of polyamide surface in the thin-layer chromatography of phenols☆

Abstract The chromatographic behaviour of some 2-substituted alkylphenols on cellulose impregnated with polyamide (10%) as the stationary phase with (a) cyclohexane—acetic acid (93:7, v/v) and (b) aqueous acetic acid (10%, v/v) as the mobile phase has been studied. The results obtained are compared with those obtained from adsorption chromatography, and reversed-phase thin-layer chromatography. The mechanism of the chromatographic process is explained in terms of the breaking of the phenolic/polyamide hydrogen bonds as a result of (i) solvation of the hydrophobic part of the molecule with the non-aqueous solvent (a), or (ii) solvation of the phenolic group with the aqueous solvent (b). The hypothesis of the duality of behaviour of polyamide is discounted.