New Visible Light-triggered Photocatalytic Trifluoromethylation Reactions of Carbon‐carbon Multiple Bonds and (Hetero)aromatic Compounds

Abstract

Visible-light-photocatalyzed methods employed insynthetic transformations present attractive properties such asenvironmentally friendly, safety, availability and excellent functionalgroup tolerance. In this venue, research on the visible-lightphotocatalytic incorporation of the trifluoromethyl CF3 moiety intoorganic substrates, in particular, has contributed to a clear evolutionof the very field of photocatalysis. Outer-sphere electron transfersbetween photocatalysts and trifluoromethyl sources supply CF3radicals efficiently in clean and controlled ways, capable of effectingnumerous synthetic transformations and functionalization on organicsubstrates and compounds with pharmacological activity instraightforward manners. Although this particular area is constantlyevolving and reviewed, the last five years have experienced anoutburst of seminal and significant photocatalytic trifluoromethylationexamples that are leading the way and opening new syntheticavenues. Recent review articles on Ru- and Ir- based photocatalytictrifluoromethylation reactions have borne witness of this evolution.Although this account will show the new Ru- and Ir-basedphotocatalytic trifluoromethylations, Sections 2 and 3 will alsoillustrate other photocatalytic systems, such as organic dyes, organicsemiconductors and newly-developed all-organic photocatalysts. All the known and reviewed strategies for photocatalytictrifluoromethylation reactions of olefins and (hetero)aromaticcompounds will not be discussed but will be summarized in twoFigures (Figures 4 and 5), and new examples (2015-present) will bepresented and discussed.