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Synlett 2018; 29(20): 2643-2647
DOI: 10.1055/s-0037-1611041
letter
© Georg Thieme Verlag Stuttgart · New York

Synthesis of 1-Aza-6,7-dehydrotropanes via Copper(I)-Catalyzed Coupling of 5-Chloropentan-2-one with Hydrazines and Terminal Alkynes

Wim E. Van Beek
a   Organic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium   eMail: Kourosch.AbbaspourTehrani@uantwerpen.be
,
Karel Weemaes
a   Organic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium   eMail: Kourosch.AbbaspourTehrani@uantwerpen.be
,
Wouter A. Herrebout
b   Research group Molecular Spectroscopy, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
,
Christophe M. L. Vande Velde
c   Faculty of Applied Engineering, Advanced Reactor Technology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
,
Kourosch Abbaspour Tehrani*
a   Organic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium   eMail: Kourosch.AbbaspourTehrani@uantwerpen.be
› InstitutsangabenThis work was financed by the Agency for Innovation by Science and Technology (IWT-Flanders), the University of Antwerp (BOF), and the Hercules Foundation (project AUGE/11/029 ‘3D-SPACE: 3D Structural Platform Aiming for Chemical Excellence’).
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Publikationsverlauf

Received: 23. August 2018

Accepted after revision: 25. September 2018

Publikationsdatum:
24. Oktober 2018 (online)

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Abstract

A one-pot, three-component, Cu(I)-catalyzed coupling of primary hydrazines, 5-chloropentan-2-one, and terminal alkynes was developed. The resulting 1-aza-6,7-dehydrotropanes compose a new class of substances while related 1-azatropanes are scarcely described in literature and closely resemble tropane alkaloids. Hydrogenation of the double bond in 1-aza-6,7-dehydrotropanes triggered a rearrangement, involving a [1,3]-hydride shift, forming cyclic hydrazones.

Key words

multicomponent reactions - alkynes - hydrazines - ketones - copper catalysis - 1-azatropanes

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1611041.
  • Supporting Information
 

  • References and Notes

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