Thin Layer Chromatographic Separation and Characterization of N-Ethyl-p-Menthane-3-Carboxamide

Conditions of TLC separation and characterization of crude product in the synthesis of N-Ethyl-p-menthane-3-carboxamide were studied.Silicagel H (type 60) was used as adsorbent supported on the thin layer chromatographic plate,which was activated at 110 ℃ for 2 h.Mixed solvent containing petroleum ether and acetone in the ratio of 5 to 1 (by volume) was used as eluant,with least eluting distance of 14.00 cm,and 4 components in the crude product were well separated.By spraying the developed thin layer with potassium iodobismuthate (KBiI4) solution and alkaline potassium permangnate (KMnO4) solution as color reagents,4 colored spots were observed clearly with their Rf values of 0.82,0.67,0.50 and 0.33.The component of the spot with Rf 0.33 was taken for elementary analysis,and as shown by the analytical results,the component was proved to be the N-ethyl-p-menthane-3-carboxamide.