Jump to main content
Jump to site search


Uncatalyzed conjugate addition of organozinc halides to enones in DME: a combined experimental/computational study on the role of the solvent and the reaction mechanism

Author affiliations

Abstract

Both aryl and alkylzinc halides prepared by direct insertion of zinc into organic halides in the presence of LiCl underwent the conjugate addition reaction to nonenolizable unsaturated ketones in excellent yield, provided that DME was used instead of THF as the solvent. Diffusion NMR measurements highlighted that the species undergo considerable aggregation under the experimental conditions used in the synthetic procedure, but no substantial differences have been found between the two solvents. Density functional theory calculations, prompted by the experimental aggregation study, revealed an unexpected reaction mechanism, where the coordinating capabilities of DME stabilize a transition state involving two organozinc moieties, lowering the activation energy of the reaction with respect to that seen for THF, enough to explain the fast and quantitative reactions observed experimentally and the different behaviors of the two solvents.

Graphical abstract: Uncatalyzed conjugate addition of organozinc halides to enones in DME: a combined experimental/computational study on the role of the solvent and the reaction mechanism

Back to tab navigation

Supplementary files

Publication details

The article was received on 24 Sep 2019, accepted on 09 Nov 2019 and first published on 11 Nov 2019


Article type: Edge Article
DOI: 10.1039/C9SC04820K
Chem. Sci., 2020, Advance Article
  • Open access: Creative Commons BY-NC license
    All publication charges for this article have been paid for by the Royal Society of Chemistry

  •   Request permissions

    Uncatalyzed conjugate addition of organozinc halides to enones in DME: a combined experimental/computational study on the role of the solvent and the reaction mechanism

    G. Casotti, G. Ciancaleoni, F. Lipparini, C. Nieri and A. Iuliano, Chem. Sci., 2020, Advance Article , DOI: 10.1039/C9SC04820K

    This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material and it is not used for commercial purposes.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements