アミノカルベンの結合による3座標鉄 (IV) ビシミド複合体:合成,構造,および反応性
Lei Wang1, Lianrui Hu2, Hezhong Zhang1
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, P. R. China.
Journal of the American Chemical Society
|October 28, 2015
まとめ
新しい鉄 (IV) ビシミド複合体は合成され,特徴づけられ,アルカン脱水化とSi-H結合活性化におけるユニークな反応性を明らかにした. これらの発見は,触媒における高価鉄中間物質の理解を進めている.
科学分野:
- 有機金属化学
- カタリシス
- 無機化学
背景:
- 高価鉄イミド種は,鉄触媒反応において極めて重要な,しかし稀な反応性中間物質である.
- 新しい触媒変換の開発には,それらの構造と反応性を理解することが不可欠です.
研究 の 目的:
- 新しい3座標鉄のビシミド複合体を合成し,特徴づけること.
- 主要な化学変換におけるこれらの複合体の反応性を調査する.
主な方法:
- 鉄 ((IV) イミド複合体を鉄 ((0) 前駆体および有機アジドから合成する.
- NMRスペクトロスコーピー,モースバウアースペクトロスコーピー,X線微分を用いた特徴付け.
- アルカン脱水化,Si-H結合活性化,サイクル添加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:
- 低スピンのシングレット基底状態の4つの新しい鉄 (IV) イミド複合体を合成し,特徴づけました.
- 分子内アルカン脱水とSi-H結合の活性化を含む独特の反応性を示した.
- [2+2]加算反応とグループ移転反応を観察した.
- DFTの計算は,観察された反応のメカニズム的な洞察を明らかにし,トリプルトウェイの好みを強調しました.
結論:
- 鉄のイミド複合体の低座標性およびd(4) 電子数は,それらのユニークな反応性の鍵です.
- これらの発見は,困難な変換のための新しい鉄ベースの触媒の設計のための基礎を提供します.
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