Synthesis 2025; 57(22): 3488-3496
DOI: 10.1055/a-2669-5931
Paper

Tropylium-Catalyzed Domino Reactions for the Thioetherification of Levoglucosenone

Autoren

  • Alexander J. Notzon

    1   Science and Technology, University of New England, Armidale, Australia
  • Oscar Lamb

    2   Faculty of Medicine and Health, University of New England, Armidale, Australia
  • Christopher J. Sumby

    3   Department of Chemistry and the Centre for Advanced Nanomaterials, School of Physics, Chemistry and Earth Sciences, University of Adelaide, Adelaide, Australia
  • Amir Karton

    1   Science and Technology, University of New England, Armidale, Australia
  • Robert J. O’Reilly

    1   Science and Technology, University of New England, Armidale, Australia
  • Ben W. Greatrex

    2   Faculty of Medicine and Health, University of New England, Armidale, Australia

OL thanks the Australian Government for Research Training (RTP) and Destination Australia Program (DAP) Scholarships. CJS acknowledges the Australian Research Council for Linkage Infrastructure, Equipment and Facilities funding (LE210100163).
Gefördert durch: Destination Australia Program (DAP)
Gefördert durch: Australian Research Council LE210100163


Graphical Abstract

Abstract

Approaches to substitute the chiral platform chemicals levoglucosenone and Cyrene with aryl and alkylthiols have been developed via the α-haloketones. Substitution of the 3-chloroalkene was catalyzed by Lewis acids, with the tropylium cation showing excellent activity and yield. When thiolate was replaced with methoxide, an alkoxyoxirane could be isolated, suggesting an analogous mechanism for the thiol substitution reaction. Substitution of the 3-bromo derivative of Cyrene with thiolate nucleophiles proceeded with retention of configuration in high yield, with an intermediate oxirane also demonstrated when using methoxide. Computed LUMO energies for the α-haloketones support pathways dependent on the type of halogen, with large contributions at the carbonyl, and a sterically inaccessible σ* orbital due to the bicyclic ring system.

Primary Data



Publikationsverlauf

Eingereicht: 11. Juni 2025

Angenommen nach Revision: 28. Juli 2025

Accepted Manuscript online:
28. Juli 2025

Artikel online veröffentlicht:
20. August 2025

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