Synlett 2003(5): 0663-0666
DOI: 10.1055/s-2003-38362
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

[2,3]-Wittig Sigmatropic Rearrangement of γ-Allyloxy-β-Enaminoesters

Isabelle Pévet, Christophe Meyer*, Janine Cossy
Laboratoire de Chimie Organique, associé au CNRS, ESPCI, 10 rue Vauquelin, 75231 Paris Cedex 05, France
Fax: +33(1)40794660; e-Mail: christophe.meyer@espci.fr;
Further Information

Publication History

Received 22 January 2003
Publication Date:
28 March 2003 (online)

Abstract

The dianions derived from γ-allyloxy-β-enaminoesters undergo a [2,3]-Wittig sigmatropic rearrangement leading to γ-hydroxy-β-enaminoester derivatives, which can be subsequently lactonized to the corresponding 4-aminofuran-2(5H)-ones.

    References

  • 1a Effenberger F. Syed J. Tetrahedron: Asymmetry  1998,  9:  817 
  • 1b Bühler H. Bayer A. Effenberger F. Chem.-Eur. J.  2000,  6:  2564 ; and references cited therein
  • 2a Hiyama T. Oishi H. Saimoto H. Tetrahedron Lett.  1985,  26:  2459 
  • 2b Hiyama T. Oishi H. Suetsugu Y. Nishide K. Saimoto H. Bull. Chem. Soc. Jpn.  1987,  60:  2139 
  • 2c Syed J. Förster S. Effenberger F. Tetrahedron: Asymmetry  1998,  9:  805 
  • 2d Wang J. Jiang X. Chen M. Ge Z. Hu Y. Hu H. J. Chem. Soc., Perkin Trans. 1  2001,  66 ; and references cited in these articles
  • 3a Greenhill JV. Ramli M. Tomassini T. J. Chem. Soc., Perkin Trans. 1  1975,  588 
  • 3b Boosen K.-J. Helv. Chim. Acta  1977,  60:  1256 
  • 3c Schmidt RR. Talbiersky J. Angew. Chem., Int. Ed. Engl.  1978,  17:  204 
  • 3d Momose T. Toyooka N. Nishi T. Takeuchi Y. Heterocycles  1988,  27:  1907 
  • 3e Martin MR. Mateo AI. Tetrahedron: Asymmetry  1994,  5:  1385 
  • 3f Veronese AC. Callegari R. Basato M. Valle G. J. Chem. Soc., Perkin Trans. 1  1994,  1779 
  • 4a Nishide K. Aramata A. Kamanaka T. Inoue T. Node M. Tetrahedron  1994,  50:  8337 
  • 4b Schlessinger RH. Iwanowicz EJ. Springer JP. Tetrahedron Lett.  1988,  29:  1489 
  • 4c Schlessinger RH. Mjalli AMM. Adams AD. Springer JP. Hoogsteen K. J. Org. Chem.  1992,  57:  2992 
  • 4d Schlessinger RH. Pettus TRR. Springer JP. Hoogsteen K. J. Org. Chem.  1994,  59:  3246 
  • 4e Schlessinger RH. Li Y.-J. J. Am. Chem. Soc.  1996,  118:  3301 
  • 4f Dankwardt SM. Dankwardt JW. Schlessinger RH. Tetrahedron Lett.  1998,  39:  4971 
  • 4g Dankwardt JW. Dankwardt SM. Schlessinger RH. Tetrahedron Lett.  1998,  39:  4979 
  • 5a Paulvannan K. Stille JR. J. Org. Chem.  1994,  59:  1613 
  • 5b Cook GR. Behloz LG. Stille JR. J. Org. Chem.  1994,  59:  3575 
  • 5c Hitotsuyanagi Y. Kobayashi M. Fukuyo M. Takeya K. Itokawa H. Tetrahedron Lett.  1997,  38:  8295 
  • 6 Pévet I. Meyer C. Cossy J. Tetrahedron Lett.  2001,  42:  5215 
  • 7a Aberhart DJ. Lin H.-J. J. Org. Chem.  1981,  46:  3749 
  • 7b Shieh T.-L. Lin C.-T. McKenzie AT. Byrn SR. J. Org. Chem.  1983,  48:  3103 
  • 7c Melillo DG. Cvetovich RJ. Ryan KM. Sletzinger M. J. Org. Chem.  1986,  51:  1498 
  • 7d Hiyama T. Kobayashi K. Nishide K. Bull. Chem. Soc. Jpn.  1987,  60:  2127 
  • 7e Pawlak JM. Khau VV. Hutchison DR. Martinelli MJ. J. Org. Chem.  1996,  61:  9055 
  • 7f Soloshonok VA. Kukhar VP. Tetrahedron  1996,  52:  6953 
  • 7g Cavé C. Gassama A. Mahuteau J. d’Angelo J. Riche C. Tetrahedron Lett.  1997,  38:  4773 
  • Although the deprotonation of tertiary β-enaminoesters at the γ-position (including N,N-disubstituted 4-aminofuran-2-(5H)-ones)4 is well-documented, the double metalation of primary or secondary ones has not been reported to our knowledge. See:
  • 8a Schlessinger RH. Iwanowicz EJ. Springer JP. J. Org. Chem.  1986,  51:  3073 
  • 8b Schlessinger RH. Li Y.-J. Von Langen DJ. J. Org. Chem.  1996,  61:  3226 
  • 8c Schlessinger RH. Gillman KW. Tetrahedron Lett.  1996,  37:  1331 
  • 8d Dankwardt JW. Dankwardt SM. Schlessinger RH. Tetrahedron Lett.  1998,  39:  4983 
  • 8e Schlessinger RH. Pettus LH. J. Org. Chem.  1998,  63:  9089 
  • 8f Schlessinger RH. Gillman KW. Tetrahedron Lett.  1999,  40:  1257 
  • General reviews on the [2,3]-Wittig rearrangement:
  • 12a Nakai T. Mikami K. Chem. Rev.  1986,  86:  885 
  • 12b Marshall JA. In Comprehensive Organic Chemistry   Vol. 3:  Trost BM. Fleming I. Pergamon Press; Oxford: 1991.  p.975-1014  
  • 12c Brückner R. In Comprehensive Organic Chemistry   Vol. 6:  Trost BM. Fleming I. Pergamon Press; Oxford: 1991.  p.873-907  
  • 12d Kallmerten J. In Houben-Weyl, Methods of Organic Chemistry   Vol. E 21d:  Helmchen G. Hoffmann RW. Mulzer J. Schaumann E. Thieme-Verlag; Stuttgart: 1995.  p.3757-3809  
  • 13a Takahashi O. Mikami K. Nakai T. Chem. Lett.  1987,  69 
  • 13b Sudo A. Hashimoto Y. Kimoto H. Hayashi K. Saigo K. Tetrahedron: Asymmetry  1994,  5:  1333 
  • 13c Enders D. Backhaus D. Synlett  1995,  631 
  • 13d Enders D. Backhaus D. Runsink J. Tetrahedron  1996,  52:  1503 
  • 13e Enders D. Bartsch M. Runsink J. Synthesis  1999,  243 
  • 13f Kress MH. Yang C. Yasuda N. Grabowski EJJ. Tetrahedron Lett.  1997,  38:  2633 
  • 13g Hiersemann M. Lauterbach C. Pollex A. Eur. J. Org. Chem.  1999,  2713 
  • 13h Hiersemann M. Tetrahedron  1999,  55:  2625 
9

Due to their moderate stability on silica gel, the β-enamino-esters 5a-c and 8 were conveniently engaged in the rearrangement step without further purification and therefore an excess of n-BuLi (4 equiv) was routinely used in order to ensure an efficient metalation process of these crude compounds at -78 °C. The nucleophilic addition of
n-BuLi to the ester carbonyl group of lithiated β-enamino-esters, and/or N,O-dilithiated β-enaminoesters arising from the [2,3]-sigmatropic rearrangement, has never been observed as a side reaction. The fact that these species may be considered as vinylogous lithiated carbamates probably accounts for their low reactivity towards n-BuLi.

10

Due to the complexity of the NMR spectra of the mixture of 6c and 6′c (presence of Z/E isomers in equilibrium for each diastereomer), the diastereomeric ratio (6c/6′c) was evaluated by GC-MS after calibration with authentic samples prepared by condensation of (R)-α-methyl-benzylamine with the γ-trimethylsilyloxy-β-ketoester 10 resulting from the [2,3]-Wittig rearrangement of 1 and subsequent silylation with TMSCl (Scheme [8] ). [6]

11

The diastereomeric ratio (7c/7′c)was determined by 1H NMR. These two diastereomers were separated and hydrolyzed to the corresponding enantiomeric tetronic acids (+)-11 and (-)-11 respectively. The (5R) absolute configuration of tetronic acid (+)-11 was assigned after hydrogenation, by correlation with the known optically pure (5R)-5-propyltetronic acid (+)-12 (Scheme [9] ). [1a]