Supramolecular Storage and Controlled Photorelease of an Oxidizing Agent using a Bambusuril Macrocycle.

The oxidizing ability of peroxodisulfate upon complexation inside the Bambusuril macrocycle cavity is inhibited. This dianionic agent can be released on demand from its stable 1:1 complex in water (log Ka =6.9 m-1 ) by addition of a more strongly bound anion, such as iodide (log Ka =7.1 m-1 ), which can also be delivered in situ upon irradiation from a 4-hydroxyphenacyl iodide derivative with spatial and temporal precision. The oxidizing properties of peroxodisulfate ions liberated from the complex recover and can take part in subsequent chemical transformations.