サイクロトリシルエニリウムイオン:パーシラロマティック化合物
Masaaki Ichinohe1, Masayasu Igarashi, Kaori Sanuki
1Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|July 14, 2005
まとめ
研究者は,サイクロプロペニリウムイオンの最初の分離可能なシリコンアナログを合成し,非常に混雑したサイクロトリシレニリウムイオンである. この新しいシリコン化合物は,X線結晶学とスペクトルデータによって確認された2pi電子の芳香性を表しています.
科学分野:
- オーガノシリコン化学 化学
- メイングループ 化学
- アロマティック性研究
背景:
- サイクロプロペニリウムイオンは,三つ組の環と2つのパイ電子を持つユニークな芳香系である.
- カーボカチオンの安定したシリコンの類型は,シリコンの電陽性とステリック要求により,合成および特徴づけに困難です.
研究 の 目的:
- サイクロプロペニリウムイオンの最初の分離可能なシリコンコンジェナーを合成し,特徴づけること.
- 新型サイクロトリシルエニリウムイオンの構造的および電子的性質を調査する.
主な方法:
- ステリカルに阻害されたサイクロトリシレンの前駆体合成.
- トリフェニルメチリウムテトラアリルボレート塩との反応により,サイクロトリシルエニリウムイオンが形成されます.
- テトラアリルボラート塩のX線結晶学とスペクトロスコピーの技術による分離と特徴付け.
主要な成果:
- 非常に混雑した3,3-bis ((di-tert-butylmethylsilyl) -1,2-bis ((tri-tert-butylsilyl) サイクロトリシレンは合成されました.
- (di-tert-butylmethylsilyl) bis ((tri-tert-butylsilyl) サイクロトリシレニウムイオンは,テトラアリルボラート塩として成功裏に分離されました.
- X線結晶学分析により,Si-Si結合の長さが2.216であるほぼ等辺の3つ構成のリングが明らかになった.
- 顕微鏡データと結晶構造は,この化合物が自由シリルカチオンと2π電子の芳香性物種であることを確認した.
結論:
- サイクロプロペニリウムイオンの最初の分離可能なシリコンアナログが合成され,特徴づけられました.
- サイクロトリシルエニリウムイオンは芳香性を発揮し,3つ構成のシリコンリングに電荷の移転を示しています.
- この研究は,シリコンを含む化合物の芳香性の理解を広げています.
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