Well-Defined β-Diketiminatocobalt(II) Complexes for Alkene Cyclohydroamination of Primary Amines

Clément Lepori, Pablo Gómez-Orellana, Allissa Ouharzoune, Régis Guillot, Agusti Lledós, Gregori Ujaque, Jérôme Hannedouche

Index: 10.1021/acscatal.8b00631

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Abstract

A well-defined low-coordinate β-diketiminatocobalt(II) alkyl complex is reported as an active precatalyst for the selective alkene cyclohydroamination of unprotected primary amines under mild conditions (rt–90 °C). The reaction mechanism has been investigated by deuterium-labeling, kinetics, and stoichiometric experiments and in-depth computational DFT studies. On the basis of these studies, we propose a stepwise noninsertive mechanism that features a rate-determining nucleophilic attack of the amido group of a monomeric cobalt(II) amidoalkene-aminoalkene adduct intermediate to the noncoordinated pendant alkene followed by a rapid proton transfer from the coordinated aminoalkene to the cyclized adduct.