Heat Engine Drives Transport of an Fe<sup>II</sup><sub>4</sub>L<sub>4</sub> Cage and Cargo
Bao‐Nguyen T. Nguyen, Angela B. Grommet, Arnaud Tron, Maureen Claire Alma Georges, Jonathan R. Nitschke
Abstract
Abstract The directed motion of species against a chemical potential gradient is a fundamental feature of living systems, underpinning processes that range from transport through cell membranes to neurotransmission. The development of artificial active cargo transport could enable new modes of chemical purification and pumping. Here, a heat engine is described that drives chemical cargo between liquid phases to generate a concentration gradient. The heat engine, composed of a functionalized Fe II 4 L 4 coordination cage, is grafted with oligoethylene glycol imidazolium chains. These chains undergo a conformational change upon heating, causing the cage and its cargo to reversibly transfer between aqueous and organic phases. Furthermore, sectional heating and cooling allow for the cage to traverse multiple phase boundaries, allowing for longer‐distance transport than would be possible using a single pair of phases.