Synlett 2011(11): 1618-1622  
DOI: 10.1055/s-0030-1260785
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Further Developments of an Enantioselective Palladium-Catalyzed Polyene Cyclization: Surprising Solvent and Ligand Effects

Daniela Lucciola, Brian A. Keay*
Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
Fax: +1(403)2899488; e-Mail: keay@ucalgary.ca;
Further Information

Publication History

Received 29 March 2011
Publication Date:
10 June 2011 (online)

Abstract

The enantioselectivity of a Pd-catalyzed domino Heck-Mizoroki cyclization is dramatically enhanced by ligand and solvent choice. Electron-deficient ligands such as (R)-DIFLUORPHOS gave 5 in %ee values ranging from 94% ee to >99% ee. EtOH was found to be superior to other solvents traditionally used in Heck-Mizoroki reactions, generally showing increases in enantioselecti­vity when compared to toluene. It is also shown that microwave heating accelerates the reaction in either solvent and allows for a longer catalyst lifetime without eroding the %ee.

    References

  • 1a Tietze LF. Brasche G. Gericke KM. Domino Reactions in Organic Synthesis   Wiley-VCH Verlag; Weinheim: 2006. 
  • 1b Tietze LF. Chem. Rev.  1996,  96:  115 
  • 1c Chapman CJ. Frost CG. Synthesis  2007,  1 
  • For selected reviews on asymmetric Heck reactions, see:
  • 2a Shibasaki M. Vogl EM. Ohshima T. Adv. Synth. Catal.  2004,  346:  1533 
  • 2b Guiry PJ. Kiely D. Curr. Org. Chem.  2004,  8:  781 
  • 2c Dounay AB. Overman LE. Chem. Rev.  2003,  103:  2945 
  • 2d Shibasaki M. Miyazaki F. Handbook of Organopalladium Chemistry for Organic Synthesis   Negishi E. J. Wiley & Sons Inc.; New York: 2002. 
  • 3a Maddaford SP. Andersen NG. Cristofoli WA. Keay BA. J. Am. Chem. Soc.  1996,  118:  10766 
  • 3b Keay BA. Maddaford SP. Cristofoli WA. Andersen NG. Passafaro MS. Wilson NS. Nieman JA. Can. J. Chem.  1996,  75:  1163 
  • 4a Lau SYW. Keay BA. Synlett  1999,  605 
  • 4b Gorobets E. Sun G.-R. Wheatley BMM. Parvez M. Keay BA. Tetrahedron Lett.  2004,  45:  3597 
  • 4c Che D. Andersen NG. Lau SYW. Parvez M. Keay BA. Tetrahedron: Asymmetry  2000,  11:  1919 
  • 4d Hopkins JM. Gorobets E. Wheatley BMM. Parvez M. Keay BA. Synlett  2006,  3120 
  • 4e Rankic DA. Lucciola D. Keay BA. Tetrahedron Lett.  2010,  51:  5724 
  • 5a Tietze LF. Wiegand JM. Vock C. J. Organomet. Chem.  2003,  687:  346 
  • 5b Tietze LF. Wiegand JM. Vock CA. Eur. J. Org. Chem.  2004,  4107 
  • 6 Datta GK. Nordeman P. Dackenberg J. Nilsson P. Hallberg A. Larhed M. Tetrahedron Asymmetry  2008,  19:  1120 
  • 7 Mata Y. Pàmies O. Diéguez M. Chem. Eur. J.  2007,  13:  3296 
  • 8 Kaukoranta P. Källström K. Andersson PG. Adv. Synth. Catal.  2007,  349:  2595 
  • 9a Jeulin S. Duprat de Paule S. Ratovelomanana-Vidal V. Genêt J.-P. Champion N. Dellis P. Angew. Chem. Int. Ed.  2004,  43:  320 
  • 9b Jeulin S. Duprat de Paule S. Ratovelomanana-Vidal V. Genêt J.-P. Champion N. Dellis P. Proc. Natl. Acad. Sci. U.S.A.  2004,  101:  5799 
  • 10a Gabriel C. Gabriel S. Grant EH. Halstead BSJ. Mingos DMP. Chem. Soc. Rev.  1998,  27:  213 
  • 10b Hayes BI. Microwave Synthesis: Chemistry at the Speed of Light   CEM Publishing; Matthews / NC: 2002. 
  • 11 For a paper that reports higher %ee values using (S)-DIFLUORPHOS in asymmetric Domino Heck-Cyanation reactions, see: Pinto A. Jia Y. Neuville L. Zhu J. Chem. Eur. J.  2007,  13:  961 
  • 12 Allen DW. Taylor BF. J. Chem. Soc., Dalton Trans.  1982,  51 
  • 13a Beletskaya IP. Cheprakov AV. Chem. Rev.  2000,  100:  3009 
  • 13b Zhang H.-C. Daves GD. Organometallics  1993,  12:  1499 
  • 13c Sengupta S. Bhattacharya S. J. Chem. Soc., Perkin Trans. 1  1993,  1943 
  • 13d Ma S. Negishi E. J. Am. Chem. Soc.  1995,  117:  6345 
  • 13e Ohrai K. Kondao K. Sodeoka M. Shibasaki M. J. Am. Chem. Soc.  1994,  116:  11737 
  • 13f Mizoroki T. Mori K. Ozaki A. Bull. Chem. Soc. Jpn.  1971,  581 
  • 14 Lau SYW. Andersen NG. Keay BA. Org. Lett.  2001,  3:  181 
  • 15a Jensen DR. Schultz MJ. Mueller JA. Sigman MS. Angew. Chem. Int. Ed.  2003,  42:  3810 
  • 15b Sheldon RA. Arends WCE. ten Brink G. Dijksman A. Acc. Chem. Res.  2002,  35:  774