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Cycloaddition Chemistry of a Silylene-Nickel Complex toward Organic π-Systems: From Reversibility to C-H Activation.

ABSTRACT: The versatile cycloaddition chemistry of the Si-Ni multiple bond in the acyclic (amido)(chloro)silylene→Ni⁰ complex 1, [(^TMS L)ClSi→Ni(NHC)₂ ] (^TMS L=N(SiMe₃ )Dipp; Dipp=2,6-iPr₂ C₆ H₄ ; NHC=C[(iPr)NC(Me)]₂ ), toward unsaturated organic substrates is reported, which is both reminiscent of and expanding on the reactivity patterns of classical Fischer and Schrock carbene-metal complexes. Thus, 1:1 reaction of 1 with aldehydes, imines, alkynes, and even alkenes proceed to yield [2+2] cycloaddition products, leading to a range of four-membered metallasilacycles. This cycloaddition is in fact reversible for ethylene, whereas addition of an excess of this olefin leads to quantitative sp² -CH bond activation, via a 1-nickela-4-silacyclohexane intermediate. These results have been supported by DFT calculations giving insights into key mechanistic aspects.

SUBMITTER: Hadlington TJ

PROVIDER: S-EPMC7028101 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Cycloaddition Chemistry of a Silylene-Nickel Complex toward Organic π-Systems: From Reversibility to C-H Activation.

Hadlington Terrance J TJ Kostenko Arseni A Driess Matthias M

Chemistry (Weinheim an der Bergstrasse, Germany) 20200131 9

The versatile cycloaddition chemistry of the Si-Ni multiple bond in the acyclic (amido)(chloro)silylene→Ni0 complex 1, [(TMS L)ClSi→Ni(NHC)2 ] (TMS L=N(SiMe3 )Dipp; Dipp=2,6-iPr2 C6 H4 ; NHC=C[(iPr)NC(Me)]2 ), toward unsaturated organic substrates is reported, which is both reminiscent of and expanding on the reactivity patterns of classical Fischer and Schrock carbene-metal complexes. Thus, 1:1 re ...[more]

PMID: 31898825

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