- 【Updated on May 12, 2025】 Integration of CiNii Dissertations and CiNii Books into CiNii Research
- Trial version of CiNii Research Knowledge Graph Search feature is available on CiNii Labs
- 【Updated on June 30, 2025】Suspension and deletion of data provided by Nikkei BP
- Regarding the recording of “Research Data” and “Evidence Data”
The β-silicon Effects in the Solvolyses of 2-(Dimethylphenylsilyl)ethyl Systems
-
- Alam Md. Ashadul
- Institute for Materials Chemistry and Engineering, Kyushu University
-
- Uddin Md. Khabir
- Institute for Materials Chemistry and Engineering, Kyushu University
-
- Fujiyama Ryoji
- Department of Material Science, Faculty of Science, Kochi University
-
- Fujio Mizue
- Institute for Materials Chemistry and Engineering, Kyushu University
-
- Tsuno Yuho
- Institute for Materials Chemistry and Engineering, Kyushu University
Bibliographic Information
- Other Title
-
- 2-(ジメチルフェニルシリル)エチル系のソルボリシスにおけるβ-ケイ素効果
Description
It is well known that the β-silicon substituent greatly facilitates the heterolysis of the C-Lg bond by 1012-fold, which is caused by the trimethylsilyl group in an antiperiplanar conformation. The β-silicon effect has been explained in terms of either the open form that is stabilized by σ-π-hyperconjugation, or the Si-bridged form by Si-participation. We thought that these two mechanisms can be distinguished by the position of Si atom, i. e., estimation of charge by means of substituent effects of Si-aryl ring. In this work, the substituent effects on the solvolysis rates of aryl-substituted derivatives [Ar-SiMe2-CR4R3-CR1R2L where (R4 = R3 = R2 = H), (R1 = H, t-Bu, m-CF3-Ph, Ph), L = Leaving group] in 60% aq. EtOH at 50°C were analyzed by the Yukawa-Tsuno Equation. The congested α-tBu system was found to indicate an intermediate ρ value of -1.47 between the open-cation system (ρ = ca. -1.00 for R1 = Ph, m--CF3-Ph) and the Si-bridged system (ρ = -1.75 for R1 = H). Since the ρ value is changing continuously, it is concluded that the mechanism of β-silicon effect can be described as a continuous spectrum of transition state between the open cation and the Si-bridged cation based on the continuous change in the ρ value.
Journal
-
- Abstracts of Symposium on Physical Organic Chemistry
-
Abstracts of Symposium on Physical Organic Chemistry 53 (0), 26-26, 2003
The Society of Physical Organic Chemistry, Japan
- Tweet
Keywords
Details 詳細情報について
-
- CRID
- 1390282680531214592
-
- NII Article ID
- 130005011294
-
- Data Source
-
- JaLC
- CiNii Articles
-
- Abstract License Flag
- Disallowed