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Transmetalation Reactions Triggered by Electron Transfer between Organocopper Complexes.

ABSTRACT: [Cu(bipy)(C₆F₅)] reacts with most aryl iodides to form heterobiphenyls by cross-coupling, but when Rf-I is used (Rf = 3,5-dicholoro-2,4,6-trifluorophenyl), homocoupling products are also formed. Kinetic studies suggest that, for the homocoupling reaction, a mechanism based on transmetalation from [Cu(bipy)(C₆F₅)] to Cu(III) intermediates formed in the oxidative addition step is at work. Density functional theory calculations show that the interaction between these Cu(III) species and the starting Cu(I) complex involves a Cu(I)-Cu(III) electron transfer concerted with the formation of an iodine bridge between the metals and that a fast transmetalation takes place in a dimer in a triplet state between two Cu(II) units.

SUBMITTER: Lozano-Lavilla O

PROVIDER: S-EPMC8609523 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Transmetalation Reactions Triggered by Electron Transfer between Organocopper Complexes.

Lozano-Lavilla Olmo O Gómez-Orellana Pablo P Lledós Agustí A Casares Juan A JA

Inorganic chemistry 20210714 15

[Cu(bipy)(C6F5)] reacts with most aryl iodides to form heterobiphenyls by cross-coupling, but when Rf-I is used (Rf = 3,5-dicholoro-2,4,6-trifluorophenyl), homocoupling products are also formed. Kinetic studies suggest that, for the homocoupling reaction, a mechanism based on transmetalation from [Cu(bipy)(C6F5)] to Cu(III) intermediates formed in the oxidative addition step is at work. Density functional theory calculations show that the interaction b ...[more]

PMID: 34259512

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