Currently, evolution of chemical transformations by visible light irradiation is highly desirable from cost,
safety, availability, and environmental friendliness points of view. Besides, activation of less reactive substrates
under very mild conditions becomes one of the most challenging tasks in organic synthesis.
However, the insufficient energy provided by one photon of visible light for their activation definitely
makes necessary the development of new protocols together with the design of new photocatalytic
systems to overcome this limitation. In this context, the implementation of biphotonic processes has
been found to be a solution for these drawbacks. This new mechanistic paradigm which combines light
upconversion processes with energy/electron transfers holds great potential for high energy demanding
bond activations, expanding the accessible reactivity window. Here, we wish to highlight the recent applications
of biphotonic processes in organic synthesis.
