An investigation of the Lewis acid mediated 1,3-dipolar cycloaddition between N-benzyl-C-(2-pyridyl)nitrone and allylic alcohol. Direct entry to isoxazolidinyl C-nucleosides

Org Biomol Chem. 2003 Jul 7;1(13):2336-42. doi: 10.1039/b304112c.

Abstract

The cycloaddition reaction of N-benzyl C-(2-pyridyl) nitrone with allylic alcohol has been carried out to obtain the corresponding 2-benzyl-3-(2-pyridyl)-5-hydroxymethylisoxazolidine. The influence of Lewis acids in the reaction has been studied and a complete 3,5-regioselectivity and cis diastereoselectivity was observed when the reaction was carried out with 1.0 equiv of AgOTf, [Ag(OClO3)(PPh2Me)] or Zn(OTf)2. Insight into the mechanism of the reaction has been obtained by isolating and characterizing (X-ray) the intermediate complexes. Also, a model based on both experimental and theoretical results is proposed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acids / chemistry*
  • Catalysis
  • Crystallography, X-Ray
  • Cyclization
  • Isoxazoles / chemical synthesis*
  • Models, Chemical
  • Molecular Structure
  • Nitrogen Oxides / chemical synthesis*
  • Nitrogen Oxides / chemistry
  • Nucleosides / chemical synthesis*
  • Organometallic Compounds / chemical synthesis
  • Organometallic Compounds / chemistry
  • Oxidation-Reduction
  • Propanols / chemistry*
  • Reproducibility of Results
  • Stereoisomerism
  • Time Factors

Substances

  • Acids
  • Isoxazoles
  • Nitrogen Oxides
  • Nucleosides
  • Organometallic Compounds
  • Propanols
  • nitrones
  • allyl alcohol