CIRCULAR-DICHROISM OF METHYLATED PHENOLS INCLUDED IN BETA-CYCLODEXTRIN - AN EXPERIMENTAL AND THEORETICAL-STUDY

The rotatory strength of inclusion complexes of various methyl-substit uted phenols (phenol, p-cresol, 2,6- and 3,5-dimethyl-, and 2,4,6- and 3,4,5-trimethylphenol) with beta-cyclodextrin are calculated by a com bination of molecular mechanics and semiempirical methods, and the res ults are compared to the respective experimentally induced circular di chroism spectra. In general, experimental results are nicely reproduce d, although symmetry breaking in the cyclodextrin, i.e. deviation from the ideally truncated cone-shaped structure, and the conformational f lexibility of the complexes contribute essentially to sign and strengt h of the induced circular dichroism.