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Non-innocent Role of the Halide Ligand in the Copper-Catalyzed Olefin Aziridination Reaction.

ABSTRACT: In the context of copper-catalyzed nitrene transfer to olefins, many systems operate upon mixing a CuX salt (X = halide, OTf) and a polydentate N-based ligand, assuming that the X ligand is displaced from the coordination sphere toward a counterion position. Herein, we demonstrated that such general assumption should be in doubt since studies carried out with the well-defined copper(I) complexes (TTM)CuCl and [(TTM)Cu(NCMe)]PF₆ (TTM = tris(triazolyl)methane ligand) demonstrate a dual behavior from a catalytic and mechanistic point of view that exclusively depends on the presence or absence of the chloride ligand bonded to the metal center. When coordinated, the turnover-limiting step corresponds to the formation of the carbon-nitrene bond, whereas in its absence, the highest barrier corresponds to the formation of the copper-nitrene intermediate.

SUBMITTER: Rodriguez MR

PROVIDER: S-EPMC10552652 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Non-innocent Role of the Halide Ligand in the Copper-Catalyzed Olefin Aziridination Reaction.

Rodríguez Manuel R MR M Rodríguez Anabel A López-Resano Sara S Pericàs Miquel A MA Díaz-Requejo M Mar MM Maseras Feliu F Pérez Pedro J PJ

ACS catalysis 20221223 1

In the context of copper-catalyzed nitrene transfer to olefins, many systems operate upon mixing a CuX salt (X = halide, OTf) and a polydentate N-based ligand, assuming that the X ligand is displaced from the coordination sphere toward a counterion position. Herein, we demonstrated that such general assumption should be in doubt since studies carried out with the well-defined copper(I) complexes (TTM)CuCl and [(TTM)Cu(NCMe)]PF<sub>6</sub> (TTM = tris(triazolyl)methane ligand) demonstrate a dual ...[more]

PMID: 37808365

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