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Updated: Jun 20, 2026

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
05:34

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes

Published on: December 16, 2019

Asymmetric intermolecular Pauson-Khand reaction of symmetrically substituted alkynes

Yining Ji1, Antoni Riera, Xavier Verdaguer

  • 1Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Institute for Research in Biomedicine and Departament de Química Orgànica, Universitat de Barcelona, c/Baldiri Reixac, 10. E-08028 Barcelona, Spain.

Organic Letters
|September 11, 2009
PubMed

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Introduction
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Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is confirmed through isotopic...