Synlett 2014; 25(14): 2019-2024
DOI: 10.1055/s-0034-1378351
letter
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Highly Functionalized Benzofuran-2-carboxamides by Ugi Four-Component Reaction and Microwave-Assisted Rap–Stoermer Reaction

Weiwei Han
a   Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. of China   Fax: +86(571)87953128   Email: chdai@zju.edu.cn
,
Jinlong Wu
a   Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. of China   Fax: +86(571)87953128   Email: chdai@zju.edu.cn
,
Wei-Min Dai*
a   Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. of China   Fax: +86(571)87953128   Email: chdai@zju.edu.cn
b   Laboratory of Advanced Catalysis and Synthesis, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, P. R. of China   Fax: +85223581594   Email: chdai@ust.hk
› Author Affiliations
Further Information

Publication History

Received: 03 May 2014

Accepted after revision: 27 May 2014

Publication Date:
09 July 2014 (online)


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

 
  • References and Notes


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