オキシランとチアランによる抽象反応におけるシリレン置換剤の影響に関する理論的研究
1School of Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, R.O.C. midesu@cc.kmu.edu.tw
Journal of the American Chemical Society
|October 10, 2002
まとめ
オキシランとチランとのシリレン反応は,特にアルキル置換剤との反応は好ましい. 脱酸素化は,シリエレンの脱硫化よりも,より熱外的であり,運動的に好ましい.
科学分野:
- コンピューティング・ケミストリー
- 反応メカニズム 反応メカニズム
- オーガノシリコン化学 化学
背景:
- シリレンは,多様な用途を持つ反応性中間物質です.
- それらの反応経路を理解することは,合成化学にとって極めて重要です.
- オキシランとチアランは,一般的なサイクルエーテルとチオエーテルです.
研究 の 目的:
- オキシランとチアランによるシリレン抽出反応の潜在エネルギー表面を調査する.
- 異なるシリレン種の相対的反応性を決定する.
- 反応エネルギーとメカニズムに対する置換物の影響を分析する.
主な方法:
- 密度関数理論 (B3LYP) の計算.
- Ab initio (QCISD) 計算について.
- 正確なエネルギー測定のためのゼロポイントの修正を含める.
主要な成果:
- 反応は,イライドのような複合体と2中心の移行状態を経由して進行する.
- アルキル置換シリレン抽出は,πドナー置換の抽出よりも有利である.
- デオキシジネーションは,脱硫化よりもエクソサーミックで運動的に有利です.
結論:
- シリレン反応性は,置換剤のタイプによって著しく影響を受けます.
- アルキル置換剤は抽象反応の好機性を高めます.
- デオキシジネーション反応は,一般的には脱硫化よりも好ましい.
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