Photocatalytic CH Activation by Hydrogen-Atom Transfer in Synthesis

This minireview encompasses the most recent (since 2010) advancements in the field of photocatalytic hydrogen-atom transfer (HAT) processes for CH bond functionalization. The direct HAT process promoted from the excited state of a photocatalyst is limited to the classes of polyoxometalates and aromatic ketones, but alternative photocatalytic strategies have recently been devised to alleviate this shortcoming, making use of indirect HAT reactions. The applications of these two approaches in organic synthesis, including the formation of CC, as well as Chalogen, CO (CO), and CN bonds, are presented herein.