Induced circular dichroism and magnetic circular dichroism spectra of maleimide and related molecules

The induced circular dichroism (ICD) spectra of the inclusion complexes of maleimide, phthatimide, and naphthalene-2,3-dicarboximide with beta- or gamma-cyclodextrin (CDx) have been measured. The structure of the CDx inclusion complexes are interpreted by the signs and shapes of ICD spectra compared with the results of PPP calculations. In maleimide and naphthalene-2,3-dicarboximide, the ICD spectra of the beta-CDx inclusion complex are very similar to those of the gamma-CDx inclusion complex in spite of the differences in dimensions between the cavity of beta-CDx and that of gamma-CDx. In phthalimide, the ICD spectra of the beta-CDx inclusion complex are very different from those of the gamma-CDx inclusion complex. The split-type ICD bands at 220 - 235 nm show that the dimer of phthalimide is formed in the presence of beta-CDx.