Oxygen-atom transfer in titanium dioxide photoredox catalysis for organic synthesis
Published:23 Sep 2016
Recent developments in organic synthesis driven by TiO2 photoredox catalysts are highlighted in this chapter. The latest discoveries indicate that TiO2, a prototypical semiconductor photoredox catalyst, is an excellent platform for O-atom transfer because (1) it is capable of adding O-atoms onto organic molecules from O2 with the assistance of electrons and (2) it is suited for removing the O-atoms from oxygen-containing molecules with the assistance of protons. Because O-atom transfer is central to the majority of organic redox transformations, understanding the mechanisms of O-atom transfer is essential to figuring out the mechanism of photoredox catalysis and the selective transformations of new organic substrates at the surface of TiO2. This highlight serves to further expand the realm of O-atom transfer (i.e., oxygenation or deoxygenation) in heterogeneous photoredox catalysis for organic synthesis.