Excitation of radical anions of naphthalene diimides in consecutive‐ and electro‐photocatalysis

Abstract

Both photo- and electrochemical transformations represent excellent opportunities for the development of environmentally friendly methodologies which, if combined, would result in improved methodologies. Thus, we present here a family of naphthalene diimide photocatalysts comparing a “pure” photochemical and an electro-photochemical transformation; by means of a C−H substitution in (hetero)aromatic systems with C−C bond formation. We identify a system that has the potential to be applied in both approaches with minor changes in the reaction conditions and recognize the excitation of radical anion of naphthalene diimides as the key event. Both approaches produce similar yields and reaction rates, although a consecutive photoinduced electron transfer (conPET) process shows in principle a simpler setup and more tolerance to a poor catalyst solubility, the electro-PET process improves selectivity and gives more room for optimization. The more accessible “pure” photochemical approach could be used as an initial assessment for photocatalytic transformation and electro-photocatalytic transformation.