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Synlett 2018; 29(20): 2643-2647
DOI: 10.1055/s-0037-1611041
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
This 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’).Further Information
Publication History
Received: 23 August 2018
Accepted after revision: 25 September 2018
Publication Date:
24 October 2018 (online)
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-azatropanesSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1611041.
- Supporting Information
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References and Notes
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