Redox-Triggered Interconversion between Piperidine Chair Conformations in a Cu(I/II) Complex

Abstract

A redox-induced six-membered ring chair-chair conformational interconversion in a copper-coordinated trans-piperidine tripodal ligand is demonstrated. Each group of the 1,2,3-substituted ring can potentially ligate the metal; two equatorial groups ligate the metal in the Cu(I) state leaving a disassociated, axial group. However, all three groups (two axial and one equatorial) ligate the metal in the Cu(II) state. Exciton-coupled circular dichroism (ECCD) and 2D NMR were used to characterize the structures.