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Synlett 2014; 25(14): 2019-2024
DOI: 10.1055/s-0034-1378351
DOI: 10.1055/s-0034-1378351
letter
Synthesis of Highly Functionalized Benzofuran-2-carboxamides by Ugi Four-Component Reaction and Microwave-Assisted Rap–Stoermer Reaction
Further Information
Publication History
Received: 03 May 2014
Accepted after revision: 27 May 2014
Publication Date:
09 July 2014 (online)
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Abstract
A two-step, diversity-oriented synthesis of highly functionalized benzofuran-2-carboxamides has been developed. The Ugi four-component reaction of aromatic amines, isocyanides, 2-bromobenzaldehyde, and 2-bromoacetic acid was used to provide a collection of N-aryl 2-bromoacetamides. The latter were then reacted with selected salicyladehydes in the presence of Cs2CO3 in acetonitrile under controlled microwave heating at 90–140 °C for 15–40 minutes to furnish the benzofuran-2-carboxamides in moderate to good yields.
Supporting Information
- for this article is available online at http://www.thieme-connect.com/products/ejournals/journal/ 10.1055/s-00000083.
- Supporting Information
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References and Notes
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