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Updated: May 23, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
A début for base stabilized monoalkylsilylenes
Ramachandran Azhakar1, Rajendra S Ghadwal, Herbert W Roesky
1Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany.
The synthesis of novel base-stabilized monoalkylsilylenes was achieved. These compounds, featuring a unique four-membered silicon-oxygen ring, open new avenues in silicon chemistry research.
Area of Science:
- Organosilicon Chemistry
- Main Group Chemistry
Background:
- Monoalkylsilylenes are reactive intermediates.
- Stabilization of silylenes is crucial for their study and application.
Purpose of the Study:
- To synthesize and characterize novel base-stabilized monoalkylsilylenes.
- To explore the reactivity of these silylenes with oxidants.
Main Methods:
- Metathesis reactions involving lithium and potassium bases with silylene precursors.
- Reaction of a synthesized silylene with nitrous oxide.
- Characterization of products using spectroscopic techniques.
Main Results:
- Successful synthesis of the first base-stabilized monoalkylsilylenes, LSitBu (2) and LSi[C(SiMe(3))(3)] (3).
- Formation of a dimer, [LSitBu(μ-O)](2) (4), containing a four-membered Si(2)O(2) ring from the reaction with N(2)O.
Conclusions:
- The developed metathesis route provides access to unprecedented base-stabilized silylenes.
- The reactivity studies demonstrate the potential for forming novel silicon-containing ring systems.
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