安定したアルキル複合体Ni (I) を製造し,その1電子酸化によりNi (II) 複合カチオンを形成する
Kristina D Kitiachvili1, Daniel J Mindiola, Gregory L Hillhouse
1Searle Chemistry Laboratory, Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|August 26, 2004
まとめ
新しいニッケル (I) アルキル複合体が合成され,ニッケル (II) カチオンに酸化されました. 予期せぬことに,これらのカチオンはガンマ-CH3デプロトン化を経て,予想されたイミドまたはフォスフィニデンの誘導体ではなく,メタラサイクロブタン製品を形成しました.
科学分野:
- 有機金属化学 有機金属化学
- ニッケル・カタリシス
- 協調化化学について
背景:
- 三座標ニッケル ((I) アルキル複合体は,価値ある合成中間物質である.
- 低価変異金属アルキルの反応性を理解することは,触媒化にとって極めて重要です.
- 以前の研究では,関連するカチオン複合体におけるアルファ-デプロトネーションが示された.
研究 の 目的:
- 新規の3座標ニッケル (((I)) アルキル複合体を合成し,特徴づけること.
- これらのニッケル複合物の酸化とその後の反応性を調査する.
- その結果生じるニッケル (((II)) カチオンのデプロトネーション経路を探求する.
主な方法:
- アルキルリチウム反応剤を用いたニッケル (((I)) アルキル複合体の合成.
- 一電子酸化により,ニッケル (ニッケル) の複合カチオン (複合カチオン) が形成されます.
- スペクトロスコピーおよび分析技術を用いた製品の特徴付け.
- デプロトン化反応の研究.
主要な成果:
- 3つの座標ニッケル ((I) アルキル複合体: (dtbpe) Ni ((CH2CMe3), (dtbpe) Ni ((CH2SiMe3),および (dtbpe) Ni ((CH2CMe2Ph) を成功裏に製造しました.
- 酸化により,安定したニッケル (((II) 複合カチオンが得られた.
- デプロトネーションは,ガンマ-CH3グループで発生し,メタラサイクロブータン製品の形成につながった.
- 観察された反応性は,類似のアミドおよびフォスフィド複合体で見られるアルファ-デプロトネーションと対照的です.
結論:
- 合成されたニッケル (((I) アルキル複合体は熱安定性を示す.
- ニッケル (II) カチオンへの酸化は容易である.
- 異常なガンマ-CH3デプロトネーション経路が観察され,金属サイクロブタンを生成した.
- この反応性は,低価ニッケル複合体の既知の化学を拡張する.
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