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; Karel Weemaes; Wouter A. Herrebout; Christophe M. L. Vande Velde; Kourosch Abbaspour Tehrani

doi:10.1055/s-0037-1611041

Synlett, Table of Contents

Synlett 2018; 29(20): 2643-2647
DOI: 10.1055/s-0037-1611041

letter

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

^aOrganic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium Email: Kourosch.AbbaspourTehrani@uantwerpen.be

,

Karel Weemaes

^aOrganic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium Email: Kourosch.AbbaspourTehrani@uantwerpen.be

,

Wouter A. Herrebout

^bResearch group Molecular Spectroscopy, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium

,

Christophe M. L. Vande Velde

^cFaculty of Applied Engineering, Advanced Reactor Technology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium

,

Kourosch Abbaspour Tehrani*

^aOrganic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium Email: Kourosch.AbbaspourTehrani@uantwerpen.be

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Abstract

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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

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References

References and Notes
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