Light as a Tool in Organic Photocatalysis: Multi‐Photon Excitation and Chromoselective Reactions
Yevheniia Markushyna, Aleksandr Savateev
Abstract
Abstract Over the past decades, photoredox catalysis has developed to the big mature field of chemistry. Especially in the field of organic synthesis, more and more sustainable alternatives to conventional synthesis are being developed. Nonetheless, most research activities are focused on the development of new synthetic pathways, utilizing photons as a source of energy for breaking and building of new chemical bonds. We discuss here cases, where selection of the irradiation mode, light intensity (one‐, two‐ photons) or wavelength (UV, blue, green) has a crucial role on the outcome of the photocatalytic event. Thus, control over irradiation conditions influence the reaction mechanism and offers an access to highly reactive species that are otherwise hardly available. This allows for the unique chemical events to happen, such as deep reduction reactions. The principles of these concepts and their applications are reviewed for both homogeneous and heterogeneous photocatalysts.