固体 (17) O NMRおよびC-ニトロゾアレン化合物の計算研究
Gang Wu1, Jianfeng Zhu, Xin Mo
1Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6. gang.wu@chem.queensu.ca
Journal of the American Chemical Society
|March 24, 2010
まとめ
この研究は,C-ニトロソーアレン化合物の最初の固体酸素-17 NMR解析を報告し,大きな四極結合定数と敏感な化学シフトテンザーを示しています. これらの発見は,固体酸素-17 NMRがすべての有機機能群に適用できると示唆しています.
科学分野:
- 固体NMRスペクトロスコーピーは,固体NMRスペクトロスコーピーを用います.
- 量子化学は量子化学である
- オーガニック化学 オーガニック化学
背景:
- Oxygen-17 NMR (17O NMR) は,分子構造と結合を調査するための強力なツールです.
- C-ニトロサアレン化合物は,特徴づけに困難であるユニークな電子構造を示しています.
- 以前の研究では,これらの化合物の17O NMRパラメータに関するデータが限られている.
研究 の 目的:
- 17OラベルのC-ニトロゾーレンの四極結合 (QC) と化学シフト (CS) テンソールの最初の固体17O NMR決定を行う.
- 有機機能群に対する固体17O NMRの適用性と検出限界を評価する.
- 実験的なNMRデータと理論的な密度関数理論 (DFT) の計算を相関させる.
主な方法:
- 17Oラベル付きC-ニトロゾアレン化合物の固体17O NMRスペクトロスコーピー.
- p-"[(17) O]ニトロソ-N,N-ジメチラニリン ([(17) O]NODMA),SnCl2(CH3) 2([(17) O]NODMA) 2 ,ZnCl2([(17) O]NODMA) 2 ,および[(17) O]NODMA.HCl.の合成について
- QCとCSテンソールの密度関数理論 (DFT) 計算. QCとCSテンソールの密度関数理論 (DFT) 計算.
- QCテンソールのタウンズ-デイリー分析.
主要な成果:
- 10〜15MHzの範囲で170の四極結合定数 (CQ) が観測され,有機化合物では最大である.
- 非常にアニソトロピックな17O CSテンソール (アニソトロピーは2800ppmまで),ニトロゾ結合系に敏感である.
- DFTの計算は,実験的な17O QCとCSテンソールを合理的に再現しました.
- 分子フレームにおける17O QCとCSテンソール方向を決定した.
- 17O CSとQCテンソーの間の内在的な関係を,N-O pi 結合順序を通じて確立しました.
結論:
- 固体17O NMRは,C-ニトロゾアレンの電子構造に対して非常に敏感です.
- このテクニックは,酸素を含む有機機能群に広く適用される可能性を示しています.
- 組み合わせた実験的および計算的アプローチは,分子結合と電子特性についての詳細な洞察を提供します.
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