`Guest-Free' Dianin's Compound

Abstract

The existence of empty hour-glass-shaped cavities is confirmed for the crystal of the title compound, 4-(p-hydroxyphenyl)-2,2,4-trimethylchroman [systematic name: 4-(2,2,4-trimethylchroman-4-yl)phenol, C 18 H 20 O 2 ]. The structure of the cavities is essentially invariant when guest molecules are intercalated. The effects of the cage structure on 13 C NMR chemical shifts of the methyl C atoms are elucidated.