A Sleeping Host Awoken by its Guest: a New Approach in Recognition and Sensing of Imidazole Containing Molecules Based on Double Cu2+ Translocation Inside a Poly-aza Macrocycle

pH-driven double Cu2+ ion translocation occurs inside an heteroditopic macrocycle. The movementopens and closes the system allowing or preventing it to function as receptor for bidentate anions. When imidazole is added to a solution buffered atan appropriate pH value, opening of the system and substrate binding can be induced by the substrate itself, which results in a sharp color change