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Synthesis 2011(21): 3429-3434  
DOI: 10.1055/s-0030-1260220
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Concise Synthesis of 3-Acetoxy-N,N-dialkylbenzo[b]thiophene-2-carboxamides from 2-Ethylsulfanylbenzoates

Kazuhiro Kobayashi*, Yuuki Kanbe, Mai Horiuchi
Division of Applied Chemistry, Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
Fax: +81(857)315263; e-Mail: kkoba@chem.tottori-u.ac.jp;
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Publication History

Received 12 July 2011
Publication Date:
13 September 2011 (online)

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Abstract

A convenient method for the synthesis of 3-acetoxy-N,N-dialkylbenzo[b]thiophene-2-carboxamides has been developed in three steps from 2-ethylsulfanylbenzoates using an interrupted Pummerer reaction of N,N-dialkyl-3-(2-ethylsulfinylphenyl)-3-oxo­propanamides. Thus, treatment of these sulfinyl amides, prepared by the reaction of 2-ethylsulfanylbenzoates with lithium enolates of N,N-dialkylacetamides followed by oxidation of the resulting N,N-dialkyl-3-(2-ethylsulfanylphenyl)-3-oxopropanamides with sodium metaperiodate and acetic anhydride at 100 ˚C leads to the formation of the desired benzo[b]thiophenes.

Key words

3-acetoxybenzo[b]thiophene-2-carboxamides - 2-ethylsulfanylbenzoates - interrupted Pummerer reaction - sulfoxides - acetic anhydride

    References

  • 1 Kobayashi K. Horiuchi M. Fukamachi S. Konishi H. Tetrahedron  2009,  65:  2430 
    CrossrefGoogle Scholar
  • 2a Svodoba J. Nic M. Palecek J. Collect. Czech. Chem. Commun.  1993,  58:  592 
    Google Scholar
  • 2b Cabiddu MG. Cabiddu S. Cadoni E. Demontis S. Fattuoni C. Melis S. Tetrahedron  2002,  58:  4529 
    Google Scholar
  • 3 Moretto AF. Kirincich SJ. Xu WX. Smith MJ. Wan Z.-K. Wilson DP. Follows BC. Binnun E. Joseph-McCarthy D. Foreman K. Erbe DV. Zhang YL. Tam SK. Tam SY. Lee J. Bioorg. Med. Chem.  2006,  14:  2162 ; and pertinent references cited therein
    CrossrefPubMedGoogle Scholar
  • 4a Boschelli DH. Kramer JB. Conner DT. Lesch ME. Schrier DJ. Ferin MA. Wright CD. J. Med. Chem.  1994,  37:  717 
    Google Scholar
  • 4b Lee J, Kirincicch SJ, Smith MJ, Wilson DP, Follows BC, Wan Z.-K, Joseph-Mccarthy DM, Erbe DV, Zhang Y.-L, Xu W, and Tam SY. inventors; Patent PCT Int. Appl. WO  2005081960.  ; Chem. Abstr. 2005, 143, 266909
  • 4c Knieps S, Dedio J, Heitsch H, Czechtiaky W, Grueneberg S, Shimshock S, Kosley R, Lanter C, Li H, Sher R, and Weichsel AA. inventors; European Patent Appl. EP  1676834.  ; Chem. Abstr. 2006, 145, 124339
  • 4d Sasikumar TK. Burnett DA. Zhang H. Smith-Torhan A. Fawzi A. Lachowicz JE. Bioorg. Med. Chem. Lett.  2006,  16:  4543 
    Google Scholar
  • 4e Hachtel S, Dedio J, Defossa E, Gruneberg S, Heitsch H, Bock W, Chen C, Kosely R, Kung C.-Y, Patek M, Sher R, Shimshock S, and Weichsel A. inventors; Patent PCT Int. Appl. WO  2008000409.  ; Chem. Abstr. 2008, 148, 121477
  • 4f Bissantz C, Grundschober C, Masciadn R, Ratni H, Rogers-Evans M, and Schnider PA. inventors; Patent PCT Int. Appl. WO  2008077811.  ; Chem. Abstr. 2008, 149, 128741
  • 5 Lau CK. Bélanger PC. Dufresne C. Scheigetz J. J. Org. Chem.  1987,  52:  1670 
    CrossrefGoogle Scholar
  • 6 Sarker M. Shahrin T. Steinmetz MG. Org. Lett.  2011,  13:  872 
    CrossrefGoogle Scholar
  • 7 Abe H. Fujii H. Masunari C. Itani J. Kashino S. Shibaike K. Harayama T. Chem. Pharm. Bull.  1997,  45:  778 
    CrossrefGoogle Scholar