Efficient enantiomeric synthesis of pyrrolidine and piperidine alkaloids from tobacco

J Org Chem. 2001 Sep 21;66(19):6305-12. doi: 10.1021/jo010386b.

Abstract

An enantiomeric synthesis of six piperidine and pyrrolidine alkaloids, (S)-nornicotine 1, (S)-nicotine 2, (S)-anatabine 3, (S)-N-methylanatabine 4, (S)-anabasine 5, and (S)-N-methylanabasine 6, known as natural products in tobacco, was established from a common chiral homoallylic (S)-3-(1-azido-but-3-enyl)-pyridine 15. An intramolecular hydroboration-cycloalkylation of the homoallylic azide intermediate 15 served as the key step in the pyrrolidine ring formation. A ring closing metathesis reaction (RCM) of a diethylenic amine intermediate (S)-allyl-(1-pyridin-3-yl-but-3-enyl)-carbamic acid benzyl ester 20 served as the key step in the piperidine ring formation. From the commercially available 3-pyridinecarboxaldehyde 13, a short and convenient enantiomeric synthesis of tobacco alkaloids is described: (S)-nornicotine 1 (5 steps, with an overall yield of 70%), (S)-nicotine 2 (6 steps, 65%), (S)-anatabine 3 (8 steps, 30%), (S)-N-methylanatabine 4 (8 steps, 25%), (S)-anabasine 5 (8 steps, 35%), and (S)-N-methylanabasine 6 (8 steps, 25%).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / chemical synthesis*
  • Alkaloids / isolation & purification
  • Magnetic Resonance Spectroscopy
  • Molecular Conformation
  • Nicotiana / chemistry*
  • Piperidines / chemistry*
  • Piperidines / isolation & purification
  • Plants, Toxic*
  • Pyrrolidines / chemistry*
  • Pyrrolidines / isolation & purification

Substances

  • Alkaloids
  • Piperidines
  • Pyrrolidines
  • piperidine
  • pyrrolidine