Synthesis 2003(17): 2740-2742  
DOI: 10.1055/s-2003-42430
PSP
© Georg Thieme Verlag Stuttgart · New York

B-Alkylcatecholboranes as a Source of Radicals for Efficient Conjugate Additions­ and Allylations

Arnaud-Pierre Schaffner, Barbara Becattini, Cyril Ollivier, Valéry Weber, Philippe Renaud*
University of Berne, Department of Chemistry and Biochemistry, Freiestrasse 3, 3000 Berne 9, Switzerland
Fax: +41(31)6313426; e-Mail: [email protected];
Further Information

Publication History

Received 11 September 2003
Publication Date:
14 October 2003 (online)

Abstract

B-Alkylcatecholboranes, easily prepared in situ by hydroboration of alkenes, are powerful radical precursors that can be used for carbon-carbon bond formation. Typical procedures for (a) conjugate addition to enones, (b) conjugate addition to activated alkenes such as vinyl sulfones, and (c) direct allylation are described. Experimentally, these three one-pot reactions are easy to perform. No slow addition of a reagent, a procedure frequently encountered in intermolecular radical additions, is required.

    References

  • 1 Yorimitsu H. Oshima K. In Radicals in Organic Synthesis   Vol. 1:  Renaud P. Sibi MP. Wiley-VCH; Weinheim: 2001.  p.11 
  • 2 Ollivier C. Renaud P. Chem. Rev.  2001,  101:  3415 
  • 3 Ollivier C. Renaud P. Chem.-Eur. J.  1999,  5:  1468 
  • 4 Ollivier C. Chuard R. Renaud P. Synlett  1999,  807 
  • 5 Ollivier C. Renaud P. Angew. Chem. Int. Ed.  2000,  39:  925 
  • 6 Cadot C. Dalko PI. Cossy J. Ollivier C. Chuard R. Renaud P. J. Org. Chem.  2002,  67:  7193 
  • 7 Becattini B. Ollivier C. Renaud P. Synlett  2003,  1485 
  • 8 Renaud P. Ollivier C. Weber V. J. Org. Chem.  2003,  68:  5769 
  • 9 Schaffner A.-P. Renaud P. Angew. Chem., Int. Ed.  2003,  42:  2658 
  • 10 Cadot C. Cossy J. Dalko PI. Chem. Commun.  2000,  1017 
  • 11 Garett CE. Fu GC. J. Org. Chem.  1996,  61:  3224