Redox-controlled molecular flipper based on a chiral Cu complex. 
A molecular bipaddled flipper based on a tetradentate chiral Cu complex has been designed.  The paddling motion of this unprecedented molecular-scale machine can be controlled by reversible oxidation of the metal center.  Kinetic and computational (density functional theory) analyses provide a detailed picture of the flipper motion at the molecular scale, rationalize the switching role of the metal-ion oxidation state, and pose the basis for the fine-tuning of the dynamic motion of this new class of molecular-scale devices.