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Synlett 2003(9): 1283-1286
DOI: 10.1055/s-2003-40336
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Dialkyl Imidazolium Benzoates - Room Temperature Ionic Liquids Useful in the Peracetylation and Perbenzoylation of Simple and Sulfated Saccharides

Saravanababu Murugesana, Nathalie Karstb, Tasneem Islamb, John M. Wienceka, Robert J. Linhardt*a-c
a Department of Chemical and Biochemical Engineering, The University of Iowa, Iowa City, IA-52242, USA
b Department of Chemistry, The University of Iowa, Iowa City, IA-52242, USA
c Department of Medicinal and Natural Products Chemistry, The University of Iowa, Iowa City, IA-52242, USA
Fax: +1(319)3356634; e-Mail: robert-linhardt@uiowa.edu;
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Publication History

Received 27 March 2003
Publication Date:
30 June 2003 (online)

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Abstract

Dialkyl imidazolium benzoates, room temperature ionic liquids including 1-ethyl-3-methyl imidazolium benzoate, 1-butyl-3-methyl imidazolium benzoate and 1-hexyl-3-methyl imidazolium benzoate were used in the peracetylation and perbenzoylation of several simple and sulfated carbohydrates. Organic solvents and catalysts were not required in the syntheses and these ionic liquids gave excellent yields in short reaction times.

Key words

carbohydrates - sulfated sugars - acylation - ionic liquids - microwave

    References

  • 1 Capila I. Linhardt RJ. Angew. Chem. Int. Ed.  2002,  41:  390 
    Google Scholar
  • 2 Kerns RJ. Vlahov IR. Linhardt RJ. Carbohydr. Res.  1995,  267:  143 
    CrossrefGoogle Scholar
  • 3 Vogel AI. Vogel’s textbook of practical organic chemistry   5th ed.:  Wiley; New York: 1984.  p.644 
    Google Scholar
  • 4 Horton WJ. Stout MG. J. Org. Chem.  1962,  27:  830 
    Google Scholar
  • 5 Chandrasekhar S. Ramachander T. Takhi M. Tetrahedron Lett.  1998,  39:  3263 
    Google Scholar
  • 6 Dupont J. Consorti CS. Spencer J. J. Braz. Chem. Soc.  2000,  11:  337 
    Google Scholar
  • 7 Seddon KR. J. Chem. Tech. Biotechnol.  1997,  68:  351 
    CrossrefGoogle Scholar
  • 8 Sheldon R. Chem. Commun.  2001,  2399 
    Google Scholar
  • 9 Forsyth AS. MacFarlane DR. Thomson RJ. Itzstein MV. Chem Commun.  2002,  714 
    Google Scholar
  • 10 Carlin RT. De Long HC. Fuller J. Trulove PC. J. Electrochem. Soc.  1994,  141:  L73 
    Google Scholar
  • 11 Holbrey JD. Seddon KR. J. Chem. Soc., Dalton Trans.  1999,  2133 
    Google Scholar
  • 12 Namboodiri VV. Varma RS. Tetrahedron Lett.  2002,  43:  5381 
    CrossrefGoogle Scholar
  • 13 NMR data: [emIm][ba]: 1H NMR (DMSO, 400 MHz) δ 1.39 (3 H, t, CH3), 3.84 (3 H, s, CH3), 4.16 (2 H, q, CH2), 7.44 (2 H, m, Ph), 7.54 (1 H, m, Ph), 7.70 (1 H, t, J = 1.7 Hz, Im), 7.79 (1 H, t, J = 1.8 Hz, Im), 7.92 (2 H, m, Ph), 9.25 (1 H, s, Im). [bmIm][ba]: 1H NMR (DMSO, 400 MHz) δ 0.91 (3 H, t, CH3), 1.28 (2 H, m, CH2), 1.78 (2 H, m, CH2), 3.88 (3 H, s, CH3), 4.20 (2 H, t, CH2), 7.49 (2 H, m, Ph), 7.60 (1 H, m, Ph), 7.77 (1 H, t, J = 1.7 Hz, Im), 7.84 (1 H, t, J = 1.7 Hz, Im), 7.96 (2 H, m, Ph), 9.36 (1 H, s, Im). [hmIm][ba]: 1H NMR (DMSO, 400MHz) δ 0.84 (3 H, t, CH3), 1.24 (6 H, m, 3 CH2), 1.76 (2 H, m, CH2), 3.84 (3 H, s, CH3), 4.14 (2 H, t, CH2), 7.16 (1 H, t, J = 1.7 Hz, Im), 7.47 (2 H, m, Ph), 7.59 (1 H, m, Ph), 7.87 (1H, t, J = 1.8 Hz, Im), 7.93 (2 H, m, Ph), 9.24 (1 H, s, Im).
  • 14 Foley KM, Griffin CC, and Amaya E. inventors; US. Pat. App,  898124. 
  • 15 Petitou M. Coudert C. Level N. Lormeau J.-C. Zuber M. Simenel C. Fournier J.-P. Choay J. Carbohydr. Res.  1992,  236:  107 
    CrossrefGoogle Scholar
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NMR data: Compound (1): 1H NMR (D2O, 400 MHz) δ 3.58 (1 H, dd, J = 7.8 Hz, 9.2 Hz, H-2), 3.62 (1 H, ddd, J = 2.1 Hz, 5.6 Hz, 9.8 Hz, H-5), 3.80 (2 H, m, H-3, H-6b), 3.95 (1 H, dd, J = 2.1 Hz, 12.5 Hz, H-6a), 4.24 (1 H, dd, J = 9.0 Hz, 9.8 Hz, H-4), 4.97 (1 H, d, J = 7.9 Hz, H-1), 7.01-7.32 (5 H, m, Ph). Compound (2): 1H NMR (D2O, 400 MHz) δ 3.43-3.51 (3 H, m, H-2, H-3, H-4), 3.69 (1 H, ddd, J = 2.0 Hz, 5.8 Hz, 7.6 Hz, H-5), 4.18 (1 H, dd, J = 5.8 Hz, 11.0 Hz, H-6b), 4.39 (1 H, dd, J = 2.0 Hz, 11.0 Hz, H-6a), 4.91 (1 H, d, J = 7.4 Hz, H-1), 7.00-7.32 (5 H, m, Ph). Compound (8): 1H NMR (D2O, 400 MHz) δ 2.04 (3 H, s, OAc), 2.05 (3 H, s, OAc), 2.06 (3 H, s, OAc), 4.98 (1 H, ddd, J = 2.5 Hz, 6.6 Hz, 9.7 Hz, H-5), 4.37 (1 H, dd, J = 6.6 Hz, 12.2 Hz, H-6b), 4.42-4.49 (2 H, m, H-4, H-6a), 5.14 (1 H, dd, J = 8.0 Hz, 9.7 Hz, H-2), 5.27 (1 H, d, J = 8.0 Hz, H-1), 5.38 (1 H, t, J = 9.7 Hz, H-3), 7.00-7.32 (5 H, m, Ph). Compound (9): 1H NMR (D2O, 400 MHz) δ 2.03 (3 H, s, OAc), 2.08 (3 H, s, OAc), 2.09 (3 H, s, OAc), 4.09-4.21 (3 H, m, H-5, H-6a, H-6b), 5.12 (1 H, t, J = 9.5 Hz, H-4), 5.21 (1 H, dd, J = 8.0 Hz, 9.5 Hz, H-2), 5.33 (1 H, d, J = 8.0 Hz, H-1), 5.42 (1 H, t, J = 9.5 Hz, H-3), 7.05-7.36 (5 H, m, Ph). Compounds (10) and (11): 1H NMR (D2O, 400 MHz) δ 4.39-4.69 (5.25 H, m, H-5α,β, H-6aα,β, H-6bα,β), 5.69 (1 H, dd, J = 3.7 Hz, 10.3 Hz, H-2α), 5.80-5.90 (2.5 H, m, H-4α, H-2β, H-4β), 6.05 (0.75 H, t, J = 9.4 Hz, H-3β), 6.30 (0.75 H, d, J = 7.9 Hz, H-1β), 6.33 (1 H, t, J = 10.0 Hz, H-3α), 6.85 (1 H, d, J = 3.7 Hz, H-1α), 8.18-7.27 (25 H, m, Ar).

17

MS (ESI): 461 [M + H+].