HV ((CO) 4 ((P-P) での異常な弱度の金属-水素結合と,H ((*) ドナーとしての効果
Jongwook Choi1, Mary E Pulling, Deborah M Smith
1Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.
Journal of the American Chemical Society
|March 14, 2008
まとめ
HV ((CO) 4 ((P-P) のV-H結合は極めて弱いため,H*をスタイレンに素早く移すことができる. これらの化合物は,1,6-ディエネを循環させるための有効な反応剤として機能する.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
背景:
- バナジウムヒドリド複合体は,触媒として知られています.
- V-H結合の反応性は,有機合成において関心があります.
研究 の 目的:
- HV(CO) 4(P-P) 複合体のV-H結合の異常な弱さを調査する.
- これらの複合物の有機変換における反応剤としての可能性を評価する.
主な方法:
- バナジウムヒドリド複合体のスペクトル学的特徴.
- H* 移転反応の運動学的研究.
- 複合体を用いた1,6-ダイエンのサイクル反応.
主要な成果:
- HV ((CO) 4 ((P-P) のV-H結合は,異常に弱い (55-58 kcal/mol) であることが判明しました.
- これらの複合体は,CpCr(CO) 3Hと比較して,スタイレンへのより速いH*転送を示しています.
- 複合体は,1,6-ダイエンのサイクル化のための効果的なステキオメトリック反応剤である.
結論:
- 弱いV-H結合が,その反応性を高めている.
- HV(CO) 4(P-P) コンプレックスは,ダイエンの循環とH* 移転反応のための有望な反応剤のクラスです.
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