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Published on: February 7, 2019
Cycloheptatriene-Fused Benzosiloles: Synthesis and Reactivity.
Kenichi Murai1, Ryuma Ochi2, Mohamed S H Salem3
1School of Pharmaceutical Sciences, Wakayama Medical University, Wakayama 640-8156, Japan.
Organic Letters
|June 15, 2026
Summary
Researchers synthesized novel cycloheptatriene-fused benzosiloles using a rhodium-catalyzed reaction. This new class of silacyclic frameworks displays unique reactivity and potential for further chemical transformations.
Area of Science:
- Organometallic Chemistry
- Synthetic Organic Chemistry
- Materials Science
Background:
- Benzosiloles are silicon-containing heterocyclic compounds with growing interest.
- Exploring novel fused ring systems can lead to new chemical properties and applications.
- Domino reactions offer efficient pathways for complex molecule synthesis.
Purpose of the Study:
- To report the synthesis of a new class of cycloheptatriene-fused benzosiloles.
- To investigate the reactivity of these novel silacyclic frameworks.
- To explore potential cationic analogues of dibenzosilole.
Main Methods:
- Rhodium-catalyzed domino cyclopropanation/Büchner ring-expansion sequence.
- Utilized biphenyl-containing silyldiazomethanes as starting materials.
- Diels-Alder trapping experiments to study cycloheptatriene-norcaradiene equilibrium.
- Oxidative conversion to generate silicon-bridged tropylium cations.
Main Results:
- Successfully synthesized cycloheptatriene-fused benzosiloles.
- Demonstrated characteristic reactivity due to cycloheptatriene-norcaradiene equilibrium.
- Generated a silicon-bridged tropylium cation, a novel cationic analogue.
- Established a new class of silacyclic frameworks.
Conclusions:
- Cycloheptatriene-fused benzosiloles represent a new class of silacyclic compounds.
- These frameworks exhibit unique reactivity patterns.
- The study opens avenues for exploring silicon-based cationic species and novel heterocyclic architectures.
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