Total synthesis 2-epi-alpha-cedren-3-one via a cobalt-catalysed Pauson-Khand reaction

William J. Kerr, Mark McLaughlin, Laura C. Paterson, Colin M. Pearson

Research output: Contribution to journalArticle

Abstract

Herein we target the total synthesis of 2-epi-alpha-cedren-3-one, a natural compound isolated from the essential oil of Juniperus thurifera. Overall, our synthetic sequence presents an optimised and robust series of chemical transformations, with prominent features including a low temperature and highly (Z)-selective Wittig olefination reaction, which is vital for the establishment of the relative stereochemistry within the final natural product, and a microwave-assisted, catalytic, intramolecular Pauson-Khand cyclisation reaction, which is used to construct the intriguing tricyclic core of the target molecule. Our optimum cyclisation protocol utilises only 20 mol% of transition metal, and delivers the complex tricyclic structure in just 10 minutes. Further manipulations of the annulation product culminate in the first total synthesis of the described natural target.
LanguageEnglish
Pages5062-5068
Number of pages7
JournalTetrahedron
Volume74
Issue number38
Early online date15 Jun 2018
DOIs
Publication statusPublished - 20 Sep 2018

Fingerprint

Cyclization
Cobalt
Juniperus
Stereochemistry
Coordination Complexes
Volatile Oils
Microwaves
Biological Products
Transition metals
Molecules
Temperature

Keywords

  • natural product
  • organic synthesis
  • catalysis
  • Pauson-Khand
  • cobalt

Cite this

Kerr, William J. ; McLaughlin, Mark ; Paterson, Laura C. ; Pearson, Colin M. / Total synthesis 2-epi-alpha-cedren-3-one via a cobalt-catalysed Pauson-Khand reaction. In: Tetrahedron. 2018 ; Vol. 74, No. 38. pp. 5062-5068.
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Total synthesis 2-epi-alpha-cedren-3-one via a cobalt-catalysed Pauson-Khand reaction. / Kerr, William J.; McLaughlin, Mark; Paterson, Laura C.; Pearson, Colin M.

In: Tetrahedron, Vol. 74, No. 38, 20.09.2018, p. 5062-5068.

Research output: Contribution to journalArticle

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