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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
A ring fragmentation approach to medium-sized cyclic 2-alkynones.
Nikolay P Tsvetkov1, Ali Bayir, Samuel Schneider
1Department of Chemistry, The University of Vermont, 82 University Place, Burlington, Vermont 05405, USA.
Organic Letters
|December 3, 2011
Summary
Bicyclic diazoketones fragment using tin(IV) chloride to yield medium-sized cyclic alkynones. This novel method efficiently produces 10-, 11-, and 12-membered alkynone products with good to excellent yields.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
Background:
- Bicyclic diazoketones are versatile synthetic intermediates.
- Accessing medium-sized cyclic compounds can be challenging.
Purpose of the Study:
- To develop a novel synthetic route to medium-sized cyclic 2-alkynones.
- To investigate the fragmentation of bicyclic γ-silyloxy-β-hydroxy-α-diazoketones.
Main Methods:
- Treatment of bicyclic γ-silyloxy-β-hydroxy-α-diazoketones with tin(IV) chloride.
- Ring fusion involving the Cβ-Cγ bond.
Main Results:
- Productive fragmentation of the bicyclic diazoketones.
- Formation of medium-sized cyclic 2-alkynones.
- Good to excellent yields for 10-, 11-, and 12-membered products.
Conclusions:
- Tin(IV) chloride-mediated fragmentation is an effective method for synthesizing medium-sized cyclic alkynones.
- This approach offers a valuable new pathway in organic synthesis.
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