結合の活性化,基板添加,および分離可能な2座標Pd(0) ビスイソシアン化モノメールによる触媒
Liezel A Labios1, Matthew D Millard, Arnold L Rheingold
1Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093-0358, USA.
Journal of the American Chemical Society
|July 28, 2009
まとめ
新しい安定した2座標のパラジウム(0) ビスイソシアニド複合体,Pd(CNAr(Dipp2)) (((2) が合成されました. この複合体は酸化添加およびクロスカップリング反応で活性であり,様々な基質とのユニークな反応性を示しています.
科学分野:
- 有機金属化学 有機金属化学
- パラジウム・カタリシス
- イソシアン化物複合体
背景:
- ゼロバルントパラジウム複合体は,触媒作用において極めて重要です.
- 安定した低座標のパラジウム複合体は,合成的に難しい.
- イソシアニドは,協調化学における多用途のリガンドである.
研究 の 目的:
- 新しい2座標パラジウム (((0) ビスイソシアン化物複合体を合成し,特徴づけること.
- この新しい複合体の反応性と触媒的応用を調査する.
- パラジウムイソシアン化物システムの電子的および構造的性質を調査する.
主な方法:
- 二価パラジウム前駆物のマグネシウム金属還元による合成.
- 温度変数 (1) H NMRとFTIRスペクトロスコーピーを用いた特徴付け.
- 酸化添加,スズキ-ミヤウラ結合,不飽和基板との反応を含む反応性研究.
- 密度関数理論 (DFT) を用いた計算分析.
主要な成果:
- 最初の安定した単体二座標パラジウム (((0) ビスイソシアン化物,Pd (((CNAr (((Dipp2)) の分離) (((2).
- トリスイソシアニド形成なしでの急速なリガンド交換の実証.
- Pd (((CNAr (((Dipp2)) (((2) は,酸化添加 (例えば,ベンジル塩化物,メシチルブロミド) と鈴木・ミヤウラ交配反応で活性を示しています.
- タリウム (((I)) トリフラート,酸素 (ペロキソ複合体を形成する),およびニトロソベンゼン (Pd (((II)) 複合体を形成する) とのユニークな反応.
結論:
- Pd (((CNAr (((Dipp2)) (((2) は,安定した低座標パラジウム化学における重要な進歩を表しています.
- 複合体は,重要な有機変異の効果的な触媒として機能します.
- ニトロソベンゼンと反応した際に正式なバレンスの変化を含む異常な反応性は,複合体のユニークな電子性質を強調しています.
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