1,4,7-トリメチロキサトリキナン:S(N) 2が三次炭素で反応する
Mark Mascal1, Nema Hafezi, Michael D Toney
1Department of Chemistry, University of California Davis, 1 Shields Avenue, Davis, California 95616, USA. mascal@chem.ucdavis.edu
Journal of the American Chemical Society
|August 5, 2010
まとめ
1,4,7-トリメチロキサトリキナンは,三次アルキルオキシオニウム塩であり,アルコール分解に抵抗するが,S(N) 2置換によるアジドと反応する. この三次炭素置換は,運動学とモデリングによってサポートされる典型的な反応パターンに挑戦します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 反応メカニズム 反応メカニズム
- 物理有機化学 物理有機化学
背景:
- 三次アルキルオキシオニウム塩は,典型的には反応性中間物質である.
- ステリー障害のあるセンターでの置換メカニズムを理解することは極めて重要です.
- 核愛置換反応におけるオクサトリキナンの行動は十分に確立されていません.
研究 の 目的:
- 1,4,7-トリメチロキサトリキナンの合成について説明する (1).
- 核愛置換に対する化合物1の反応性を調査する.
- 三次炭素中心における置換のメカニズムを解明する.
主な方法:
- 1,4,7-トリメチロキサトリキナンの合成.
- アルコールによる溶解反応.
- アジドアニオンによる核性置換反応.
- 計算モデリング.
- 運動学的研究.
- 溶媒と塩の効果分析. 溶媒と塩の効果分析.
主要な成果:
- 1,4,7-trimethyloxatriquinane (1) が成功して合成されました.
- 化合物1は,高温下でもアルコールによる溶解に惰性を示した.
- アジドアニオンとの容易な置換が発生しました.
- 証拠は,三次炭素中心の置換のためのS(N) 2メカニズムを支持し,S(N) 1.1.1を除く.
- 計算モデリングと運動データは,S(N) 2経路を裏付けている.
結論:
- S(N) 2メカニズムは,1,4,7-トリメチロキサトリキナンの三次炭素センターでの置換に有効です.
- これは,核愛置換におけるステリック阻害に関する従来の理解に異議を唱える.
- この発見は,オキシオニウム塩の反応性に関する新しい洞察を提供します.
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