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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
エクストリームオクサトリキナネス: 極めて長い炭素-酸素結合を持つα-オクシオキシオニウム種の構造的特徴
Gorkem Gunbas1, William L Sheppard, James C Fettinger
1Department of Chemistry, University of California-Davis , 1 Shields Avenue, Davis, California 95616, United States.
Journal of the American Chemical Society
|May 21, 2013
まとめ
研究者らは,初の安定したα-オキシオキシオニウム種を合成し,記録的な炭素-酸素結合長さを明らかにした. これらの発見は,アセテライゼーション反応中間物質と安定したオキシオニウムイオン化学に関する洞察を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 物理化学 物理化学について
- コンピューティング・ケミストリー
背景:
- 安定したα-オキシオキシオニウム種は,典型的には難解な中間物質である.
- 電子構造を理解することは,反応機構の解明の鍵です.
研究 の 目的:
- 最初の安定したα-オキシオキシオニウム種を合成し,特徴づけること.
- 炭素-酸素結合の長さに対する電子効果の影響を調査する.
主な方法:
- 新型オキサトリキナントリフラート誘導体の合成.
- 構造分析のためのX線結晶学.
- 電子特性を予測するための計算モデリング.
主要な成果:
- α-ヒドロキシおよびα-メトキシオクサトリキナンのトリフラートの合成と特徴づけに成功しました.
- 前例のない長いC-O(+) 結合長 (1.658 Å と 1.619 Å) の決定.
- モデリングは,強い電子の寄付が結合長に影響することを確認しました.
結論:
- 安定したα-oxyoxonium種を合成し,特徴づけることができます.
- トリキナンの枠組みは,これらの種を安定させます.
- 観測されたC-O(+) 結合の長さは,化学結合の新たな基準となる.
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