Circular dichroism spectra of amino acid complexes. III. Copper(II) compounds

Abstract

The solution circular dichroism spectra of the 1 : 1 and 1 : 2 copper(II) complexes of a series of ¿-amino acids are reported for the region 12500-25000 cm-1. These spectra and spectra of the isolated 1 : 2 complexes dispersed in KBr disks have been interpreted as arising from three Cotton effects with a -,+,- sign pattern for the L configuration, except for the L-proline spectra, which were analysed in terms of a +,-,+ pattern. A tentative assignment is made for these Cotton effects, and the relative contributions of vicinal and conformational effects to the rotational strength are discussed.