Four Oxidation States in a Single Photoredox Nickel‐Based Catalytic Cycle: A Computational Study

Abstract

Dedicated Professor Pablo Espinet on the occasion of his 70th birthdayAbstract: The computational characterization of the full catalytic cycle for the synthesis of indoline from the reaction between iodoacetanilide and at erminal alkene catalyzed by an ickel complex and ap hotoactive ruthenium species is presented. Avariety of oxidation states of nickel, Ni 0 ,Ni I ,Ni II , and Ni III ,i ss hown to participate in the mechanism. Ni 0 is necessary for the oxidative addition of the CÀIb ond, which goes through aN i I intermediate and results in aN i II species. The Ni II species inserts into the alkene,b ut does not undergo the reductive elimination necessary for CÀNb ond formation. This oxidatively induced reductive elimination can be accomplished only after oxidation to Ni III by the photoactive ruthenium species.A ll the reaction steps are computationally characterized,a nd the barriers for the single-electron transfer steps calculated using am odified version of the Marcus Theory.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

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