Control of Oxygen Atom Chirality and Chelate Ring Conformation by Protected/Free Sugar Hydroxyl Groups in Glucose-Pendant Dipicolylamine−Copper(II) Complexes

A pair of copper(II) complexes 1 and 2 exhibit an enantiomeric chiral center at the oxygen atom that coordinates to the metal center. The configurations of the oxygen atom chirality and the chelate ring conformation are simply controlled by protected/free hydroxyl groups of the sugar moiety, yielding mirror image CD spectra. In this system, repulsive and attractive forces are used to regulate chirality on the copper-coordinated oxygen atom both in the solid state and in solution.