酸化ニトリルからフロキサンへのダイメリゼーションは,ダイナトロソアルケンのダイラジカル経由で段階的に行われます:密度関数理論の研究
Zhi-Xiang Yu1, Pierluigi Caramella, K N Houk
1Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA.
Journal of the American Chemical Society
|December 11, 2003
まとめ
密度関数理論は,窒素酸化物のフロキサンへの二酸化化は,二基中 intermediates を経由して段階的に進行することを明らかにします. 芳香性ニトリル酸化物は,C−C結合形成中の結合が中断されたため,よりゆっくりと二酸化します.
科学分野:
- コンピューティング・ケミストリー
- 有機反応のメカニズム
背景:
- ニトリル酸化物は,汎用性の高い合成中間物質である.
- ニトリル酸化物の二分化によるフロキサン形成は,重要な反応である.
研究 の 目的:
- アセトニトリル酸化物とパラクロロベンゾニトリル酸化物の二酸化化のメカニズムを解明する.
- フロキサン形成におけるダイラジカル中間物質の役割を調査する.
- アロマティックニトリル酸化物における二酸化率に影響を与える要因を理解する.
主な方法:
- 密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.
- B3LYP/6-31G* コンピューティングレベル.
- 反応経路と中間物質の性質の分析
主要な成果:
- ダイメリゼーションは段階的に発生し,重要なダイラジカル特性を持つディニトロソアルケンの中間物質を形成します.
- C-C結合形成は,両方の反応の速度を決定するステップです.
- 芳香性ニトリル酸化物は,C−C結合形成中の結合が中断されたため,より遅い二極化を示す.
- 単環フロキサンのイソメリゼーションは,おそらくダイラジカルメカニズムを経由して進行する.
結論:
- ニトリル酸化物からフロキサンへの二酸化は,二基中 intermediates を含む.
- 芳香系における電子効果は反応速度に影響する.
- DFTは,複雑な有機反応機構に関する貴重な洞察を提供します.
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