Synlett 2005(15): 2405-2406  
DOI: 10.1055/s-2005-872681
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

Copper(I) Thiophene-2-carboxylate (CuTC)

Anna Innitzer*
Institute of Organic Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria
e-Mail: anna.innitzer@univie.ac.at;
Further Information

Publication History

Publication Date:
07 September 2005 (online)

Introduction

In the early 1990s, the influence of co-catalytic copper(I) salts on Stille cross-coupling reactions was reported. The copper effect soon found application in numerous other palladium-catalyzed C-C bond forming reactions. [1] As it was suggested, that the cross coupling protocol could be mediated by simple copper salts alone, [1] various copper(I) carboxylates were screened and it was shown that ­copper(I) thiophene-2-carboxylate (CuTC) mediates most efficiently intermolecular cross-coupling reactions of ­aryl, heteroaryl and vinylstannanes with vinyl iodides at low temperature in high yields. [2]

Soon, CuTC found application not only in a number of different types of cross-coupling reactions [4] [6-8] but also in enantioselective allylation reactions [10] and very recently in asymmetric 1,4-additions. [11] [12] CuTC can be easily prepared in multigram scale from thiophene-2-carboxylic acid and Cu2O upon heating in toluene and azeotropic ­removal of water (Scheme 1). The obtained product is a tan, air-stable powder, which can be stored and handled at room temperature without any special precautions. [2]

Scheme 1 Preparation of CuTC

    References

  • 1 Liebeskind LS. Fengl RW. J. Org. Chem.  1990,  55:  5359 
  • 2 Allred GD. Liebeskind LS. J. Am. Chem. Soc.  1996,  118:  2748 
  • 3 Wehlan H. Dauber M. Mujica Fernaud MT. Scuppan J. Mahrwald R. Ziemer B. Juarez Garciz ME. Koert U. Angew. Chem. Int. Ed.  2004,  43:  4597 
  • 4 Porco JA. Shen R. Org. Lett.  2000,  2:  1333 
  • 5 Baati R. Kim DW. Nicolaou KC. Angew. Chem. Int. Ed.  2002,  41:  3701 
  • 6 Liebeskind LS. Zhang S. Zhang D. J. Org. Chem.  1997,  62:  2312 
  • 7 Liebeskind LS. Srogl J. Savarin C. Org. Lett.  2001,  3:  91 
  • 8 Liebeskind LS. Srogl J. J. Am. Chem. Soc.  2000,  122:  11260 
  • 9 Magid RM. Tetrahedron  1980,  36:  1901 
  • 10 Alexakis A. Polet D. Tissot-Crosset K. Angew. Chem. Int. Ed.  2004,  43:  2426 
  • 11 Alexakis A. Polet D. Tetrahedron Lett.  2005,  46:  1530 
  • 12 Alexakis A. d’Augustin M. Palais L. Angew. Chem. Int. Ed.  2005,  44:  1376