Stereoselective synthesis of optically active cyclopenta[c]pyridines and tetrahydropyridines


Sezer S. , Gumrukcu Y., Bakirci I., Unver M. Y. , TANYELİ C.

TETRAHEDRON-ASYMMETRY, vol.23, no.9, pp.662-669, 2012 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 23 Issue: 9
  • Publication Date: 2012
  • Doi Number: 10.1016/j.tetasy.2012.04.016
  • Title of Journal : TETRAHEDRON-ASYMMETRY
  • Page Numbers: pp.662-669

Abstract

The intramolecular Pauson-Khand and ring closing metathesis (RCM) reactions of nitrogen containing chiral enynes and dienes are described. The enyne and diene systems comprised of N-propargylated and N-allylated units are constructed on chiral homoallylic or homopropargylic alcohol backbones, respectively, via S(N)2 and/or modified Mitsunobu reactions. The racemic homoallylic and homopropargylic alcohol derivatives were successfully resolved in high ee (93-99%) by applying chemoenzymatic methods using various lipases such as PS-C II, Lipozyme, and CAL-B. Each enantiomerically enriched enyne afforded the most conformationally stable diastereomeric cyclopenta[c]pyridine ring system as the sole product, whereas enantiomerically enriched dienes gave tetrahydropyridine derivatives as a result of intramolecular Pauson-Khand and RCM reactions, respectively. (C) 2012 Elsevier Ltd. All rights reserved.