Synlett 2013; 24(18): 2345-2349
DOI: 10.1055/s-0033-1338977
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© Georg Thieme Verlag Stuttgart · New York

Unsaturated Amino Alcohols via Cyclization of Allylic Bistrichloroacetimidates

Aigars Jirgensons*, Liene Grigorjeva, Ansis Maleckis, Kristine Klimovica
  • Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga 1006, Latvia   Fax: +37167550338   Email: aigars@osi.lv
Further Information

Publication History

Received: 29 July 2013

Accepted after revision: 17 September 2013

Publication Date:
14 October 2013 (eFirst)

Abstract

In intramolecular allylic substitution of bistrichloroacetimidates, one of the imidate groups can serve as a N-nucleophile while the other can serve as a leaving group, leading to 2-vinyloxazolines. Two approaches based on different mechanisms for allylic substitution can be applied to achieve cyclization of the bisimidates. The reaction, catalyzed by palladium(II), presumably involves aminometalation of the double bond followed by deoxypalladation. Enantioenriched products can be obtained using chiral palladium(II) catalysts as demonstrated for the cyclization of achiral bisimidates derived from (E/Z)-butene-1,4-diol. Allylic substitution can proceed via a competing mechanism that involves carbenium ion formation from a metal-complexed imidate. This enables the use of Lewis acids as nonexpensive and less toxic alternative to palladium catalysts. Regioselectivity of Lewis acid catalyzed bisimidate cyclization is controlled by formation of the most stable carbenium ion as proposed intermediate. This approach provides an efficient access to vinylglycinols, butadienylglycinol, and C-quaternary vinylglycinols.

 
  • References


    • Selected references:
    • 1a Muncipinto G, Moquist PN, Schreiber SL, Schaus SE. Angew. Chem. Int. Ed. 2011; 50: 8172
    • 1b Cresswell AJ, Davies SG, Lee JA, Morris MJ, Roberts PM, Thomson JE. J. Org. Chem. 2012; 77: 7262
    • 1c Joosten A, Persson AK. Å, Millet R, Johnson MT, Bäckvall J.-E. Chem. Eur. J. 2012; 18: 15151
    • 1d Ghosal P, Shaw AK. J. Org. Chem. 2012; 77: 7627
    • 1e Liang H, Zhou Y, Ciufolini M. Synthesis 2010; 2515
  • 2 For a review see: Berkowitz DB, Charette BD, Karukurichi KR, McFadden JM. Tetrahedron: Asymmetry 2006; 17: 869
  • 3 We have previously developed the Pd(II)-catalyzed cyclization of δ-acetoxy allylic imidates to vinyloxazolines: Maleckis A, Jaunzeme I, Jirgensons A. Eur. J. Org. Chem. 2009; 6407
  • 4 Sabat M, Johnson CR. Org. Lett. 2000; 2: 1089
  • 5 Maleckis A, Klimovica K, Jirgensons A. J. Org. Chem. 2010; 75: 7897

    • For leading references, see:
    • 6a Donde Y, Overman LE. J. Am. Chem. Soc. 1999; 121: 2933
    • 6b Anderson CE, Overman LE. J. Am. Chem. Soc. 2003; 125: 12412
    • 6c Jautze S, Seiler P, Peters R. Chem. Eur. J. 2008; 14: 1430
    • 6d Watson MP, Overman LE, Bergman RG. J. Am. Chem. Soc. 2007; 129: 5031
  • 7 Grigorjeva, L.; Jirgensons, A. unpublished results.
  • 8 Grigorjeva L, Maleckis A, Klimovica K, Skvorcova M, Ivdra N, Leitis G, Jirgensons A. Chem. Heterocycl. Compd. 2012; 48: 919
    • 9a Kokotos G, Chiou A. Synthesis 1997; 168
    • 9b Wessel H.-P, Iversen T, Bundle DR. J. Chem. Soc., Perkin Trans. 1 1985; 2247
    • 10a Link JT, Gallant M, Danishefsky SJ, Huber S. J. Am. Chem. Soc. 1993; 115: 3782
    • 10b Link JT, Raghavan S, Danishefsky SJ. J. Am. Chem. Soc. 1995; 117: 552
  • 11 Ramstadius C, Hekmat O, Eriksson L, Stålbrand H, Cumpstey I. Tetrahedron: Asymmetry 2009; 20: 795
  • 12 Grigorjeva L, Jirgensons A. Eur. J. Org. Chem. 2011; 2421
  • 13 Klimovica, K.; Maleckis, A.; Jirgensons, A. unpublished results.
  • 14 Klimovica K, Grigorjeva L, Maleckis A, Popelis J, Jirgensons A. Synlett 2011; 284