A new phenomenon of various polarity observed in p-menthane-1,2,4-triol

摘要

A new phenomenon was observed for p-menthane-1,2,4-triol, i.e., the substance with the same molecular structure occurs in two forms with different polarity. The form with a lower polarity is eluted with ethyl acetate in column chromatography; the form with a higher polarity is eluted with methanol. The crystals isolated by ethyl acetate elution exhibit polymorphism; whereas no polymorphism was observed for the crystals isolated by methanol elution. The crystals isolated differed in melting temperature and optical rotation. The structure of p-menthane-1,2,4-triol was confirmed by two independent methods, i.e., by the single-crystal X-ray diffraction and NMR spectra.