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Identification of the Active Catalyst for Nickel-Catalyzed Stereospecific Kumada Coupling Reactions of Ethers.

ABSTRACT: A series of nickel complexes in varying oxidation states were evaluated as precatalysts for the stereospecific cross-coupling of benzylic ethers. These results demonstrate rapid redox reactions of precatalysts, such that the oxidative state of the precatalyst does not dictate the oxidation state of the active catalyst in solution. These data provide the first experimental evidence for a Ni⁰ -Ni^II catalytic cycle for a stereospecific alkyl-alkyl cross-coupling reaction, including spectroscopic analysis of the catalyst resting state.

SUBMITTER: Dawson DD

PROVIDER: S-EPMC7872209 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Identification of the Active Catalyst for Nickel-Catalyzed Stereospecific Kumada Coupling Reactions of Ethers.

Dawson David D DD Oswald Victoria F VF Borovik Andy S AS Jarvo Elizabeth R ER

Chemistry (Weinheim an der Bergstrasse, Germany) 20200221 14

A series of nickel complexes in varying oxidation states were evaluated as precatalysts for the stereospecific cross-coupling of benzylic ethers. These results demonstrate rapid redox reactions of precatalysts, such that the oxidative state of the precatalyst does not dictate the oxidation state of the active catalyst in solution. These data provide the first experimental evidence for a Ni<sup>0</sup> -Ni<sup>II</sup> catalytic cycle for a stereospecific alkyl-alkyl cross-coupling reaction, incl ...[more]

PMID: 31953874

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