Abstract

The two 1,10-phenanthroline ligands in the mixed ?-cobalt(III) complex with sucrose are in different environments relative to the sucrose ligand as shown by differences in their 1H NMR signals and predicted by structural optimization. There is considerable congestion between the glucose moiety and one of the phenanthrolines in the ?-complex, and the interactions which stabilize it, relative to a ?-complex, are analyzed. Differences in 1H chemical shifts of the phenanthrolines are related to their mutual interactions and those with the glucose moiety of the sugar, which lead to ?-shielding in some of its 1H NMR signals. Absorption and circular dichroism (CD) spectra are analyzed with assignment of the electronic transitions. © 2002 Elsevier Science Ltd. All rights reserved.