内部分子周辺の挫折したルイスペアのフォスファン/ボランの炭基化反応
Muhammad Sajid1, Arunlibertsen Lawzer, Weishi Dong
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität , Corrensstraße 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|October 24, 2013
まとめ
内分子挫折ルイス対 (FLP) は一酸化炭素と反応する. 条件に応じて,FLPはヘテロサイクリックカルボニルまたはボランカルボニルを形成し,ユニークな反応性を示します.
科学分野:
- 有機金属化学 有機金属化学
- メイングループ 化学
- カタリシス カタリシス カタリシス
背景:
- フラストラテッド・ルイス・ペア (FLP) は,クラシック・アドクトを形成できないルイス酸塩基のペアである.
- 分子内FLPは,同じ分子内にルイス酸と塩基の両方を含む.
- 炭素一酸化物 (CO) のような小分子とのFLPの反応性は,重要な研究分野です.
研究 の 目的:
- 炭素一酸化物への分子内FLPの協力的添加を調査する.
- 反応条件 (溶液対マトリックス,温度) がFLP-COアダクト形成に及ぼす影響を調査する.
- 彼らの水素化された産物から派生したFLPのガス相の振る舞いを研究する.
主な方法:
- 分子内FLP (Mes2PCH2CH2B ((C6F5) 2) とノルボランベースのFLP) の合成と特徴付け.
- FLPと一酸化炭素の反応は,さまざまな条件下 (溶液 -35°C,アルゴンマトリックス 25 K) に行われます.
- 反応機構とエネルギー学を研究するための密度関数理論 (DFT) 計算.
主要な成果:
- 内分子FLP Mes2PCH2CH2B (((C6F5)2) は協同的にCOを添加して5基のヘテロサイクリックカルボニル化合物を形成します.
- ノルボルナン基の分子内FLPは,溶液中の5基のヘテロサイクリックFLP-カルボニル化合物を生成します.
- マトリックス分離条件下では,同じFLPは,フォスフィンの関与なしにボランカルボニルを選択的に形成します.
- DFTの研究では,溶液中のフォスフォニウムヒドリドボラートズウィテリオンがエクセルゴニックに形成され,ガス相ではH2を失う傾向があることが示されています.
結論:
- 内部分子FLPは,一酸化炭素に対して多様な反応性を発揮し,反応環境によって異なる異環状またはボランカルボニル製品を形成します.
- 分子内FLPの近接と枠組は,CO活性化経路に大きな影響を与える.
- FLPから派生した種の安定性と行動は,溶液とガス相の間に顕著に異なることがあります.
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