Photoswitchable Catalysis by a Small Swinging Molecule Confined on the Surface of a Colloidal Particle

We present a light-regulated catalytic system composed of a molecular catalyst immobilized on a nanoparticle surface via an organic photoswitch. Depending on the conformation of the photoswitch the catalytic center is hidden or exposed to reaction mixture causing changes in the reaction rate. The proposed concept of photoswitchable catalysis opens up plenty of possibilities to control not only the rate but also the order in which chemical reactions proceed to pave the way toward chemo-, regio-, and stereoselectivity.