Photochemical synthesis: Using light to build C-C bonds under mild conditions

A review of recent advancements in metal-free arylations via photogenerated triplet aryl cations and decatungstate anion ([W10O32]4−) photocatalyzed C-C bond formation is reported herein. These approaches are two examples of the great potentialities of photons as green activants in organic synthesis, allowing the functionalization of different chemical substrates under mild conditions (room temperature, aqueous solvents, absence of aggressive and unstable reactants and of expensive transition metal-based catalysts, and chance to use solar light as the energy source).