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04:38
Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Bifunctional reactivity of Cu(I): sequential ring opening/N-arylation.
Andrew Martins1, Sébastien Lemouzy, Mark Lautens
1Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6.
Organic Letters
|December 5, 2008
Summary
A novel one-pot synthesis creates N-arylaminooxazolidinones using a single copper(I) catalyst. This method reveals a cis-fused 5,5-membered ring system formation during rearrangement, confirmed by X-ray crystallography.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- N-arylaminooxazolidinones are important pharmaceutical intermediates.
- Previous synthetic routes often require multiple steps and catalysts.
- The mechanism of their formation, particularly the rearrangement step, has been debated.
Purpose of the Study:
- To develop an efficient one-pot synthesis for N-arylaminooxazolidinones.
- To investigate the stereochemical outcome of the rearrangement step.
- To clarify the mechanism of the Lewis acid catalyzed rearrangement.
Main Methods:
- One-pot sequential catalysis using a single copper(I) catalyst.
- Lewis acid catalyzed rearrangement reaction.
- N-arylation reaction.
- X-ray crystallography for structural determination.
Main Results:
- Successful one-pot synthesis of N-arylaminooxazolidinones achieved.
- A cis-fused 5,5-membered ring system was formed during the rearrangement.
- This finding contradicts previous reports on the stereochemistry of the rearrangement.
- X-ray crystallography confirmed the cis-fusion of the ring system.
Conclusions:
- The developed one-pot method offers an efficient route to N-arylaminooxazolidinones.
- The rearrangement proceeds with specific stereochemical control, forming a cis-fused system.
- This study clarifies a key mechanistic aspect of oxazolidinone synthesis.
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