パラマグネティックで単核のスーパースルフィドニッケル ((II)) 複合体から,四硫黄の2電子結合を持つ二磁気ジーマーまで
Shenglai Yao1, Carsten Milsmann, Eckhard Bill
1Metalorganics and Inorganic Materials, Institute of Chemistry, Technische Universität Berlin, Strasse des 17, Juni 135, Sekr. C2, D-10623 Berlin, Germany.
Journal of the American Chemical Society
|September 23, 2008
まとめ
研究者は,最初の分離可能なニッケル (((II) 超硫化物複合体を合成し,難解なS2-.を特徴とした. リガンド. リガンド. このパラマグネティック複合体は二重化して,独特の4つの硫黄結合を持つ二磁性種を形成します.
科学分野:
- 無機化学 無機化学とは
- 有機金属化学 有機金属化学
- 硫黄化学 硫黄の化学
背景:
- 超硫化物 (S2^2-) リガンドは高度に反応性があり,安定した協調複合体で分離することは困難である.
- 以前の研究では,超硫化物複合体の一時的またはあまり特徴のない形態に焦点を当てていた.
- 硫黄リガンドの協調化学を理解することは,触媒と材料科学にとって極めて重要です.
研究 の 目的:
- 最初の分離可能な"サイドオン"ニッケル (II) 超硫化物複合体を合成し,特徴づけること.
- 合成された超硫化物複合体とその二重体の構造的および電子的性質を調査する.
- 硫黄移転反応における超硫化物複合体の反応性を調査する.
主な方法:
- ニッケル (ニッケル) の前駆体と元素硫黄の容易酸化による合成.
- X線微分分析を用いた構造的特徴化.
- 1H NMR,EPR,およびSQUID磁気測定を含むスペクトロスコピク分析. 1H NMR,EPR,およびSQUID磁気測定を含むスペクトロスコピク分析. 1H NMR,EPR,およびSQUID磁気測定を含むスペクトロスコピク分析.
- 密度関数理論 (DFT) の計算を用いた計算研究.
主要な成果:
- 最初の分離可能な"サイドオン"ニッケル (II) 超硫化物複合体の成功合成 (1).
- パラマグネティック・スーパースルフィード複合体 (1) が,4つの硫黄,2つの電子結合を備えたダイマグネティック・ディマー (1(2) に自発的に二重化することを実証.
- スーパルスルフィード複合体の硫黄をフォスフィンリガンドとニッケル前駆体に転送し,ジスルフィード複合体を形成する能力の証拠 (3).
結論:
- この研究は,ニッケル (II) 複合体内の難解なS2^2-リガンドの安定化と分離を報告しています.
- 二重化行動は,ポリ硫化リガンドの新しい結合モードを強調しています.
- 合成された超硫化物複合体は,二硫化物複合体と硫黄移転反応の貴重な前駆体として機能する.
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