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CO2 Activation by Lewis Pairs Generated Under Copper Catalysis Enables Difunctionalization of Imines

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    CO2 Activation by Lewis Pairs Generated Under Copper Catalysis Enables Difunctionalization of Imines
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    Journal of the American Chemical Society

    Cite this: J. Am. Chem. Soc. 2020, 142, 4, 1966–1974
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    https://doi.org/10.1021/jacs.9b11423
    Published January 8, 2020
    Copyright © 2020 American Chemical Society
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    Abstract

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    Integration of distinct substrate activation modes in a catalytic circle is critical for the development of new, powerful synthetic methodologies toward complex and value-added chemicals from simple and readily available feedstocks. Here, we describe a highly selective difunctionalization of imines through incorporation of activation of CO2 by intramolecular N/B Lewis pairs into a copper catalytic cycle. Experimental and computational studies on the mechanistic aspect revealed an α-borylalkylamido intermediate, a metal amide-based Lewis pair formed by borylation of a C–N double bond, and enabled an unprecedented CO2 fixation pattern that is in sharp contrast to the traditional CO2 insertion into transition-metal-element bonds. The unique lithium cyclic boracarbamate products could be easily transformed into multifunctional N-carboxylated α-amino boronates. The highly diastereoselective reactions of chiral N-tert-butanesulfinyl aldimines were also achieved. We hope that our findings may inspire further development of selective multicomponent reactions by incorporation of Lewis pair chemistry into transition-metal catalysis.

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    This article is cited by 57 publications.

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    Journal of the American Chemical Society

    Cite this: J. Am. Chem. Soc. 2020, 142, 4, 1966–1974
    Click to copy citationCitation copied!
    https://doi.org/10.1021/jacs.9b11423
    Published January 8, 2020
    Copyright © 2020 American Chemical Society
    Request reuse permissions

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