核愛型T型 (LXL) Au (I) ピンサー複合体:プロトン化とアルキル化
George Kleinhans1, Max M Hansmann2, Gregorio Guisado-Barrios3
1Chemistry Department, University of Pretoria , Private Bag X20, Hatfield 0028, Pretoria, South Africa.
Journal of the American Chemical Society
|December 15, 2016
まとめ
研究者らは,カルバゾールとメソイオンカルベンのリガンドで新しいT型金 ((I) ピンサー複合体を合成した. これらの複合体は,電ophiles とのユニークな反応性を発揮し,異常なカチオンの金 (III) 水素種を形成する.
科学分野:
- 有機金属化学
- 協調化学
- 炭酸塩化学
背景:
- 金 ((I) 複合体は通常,電ophiles に対して制限された反応性を示します.
- ピンサー・リガンドはユニークな調整環境を提供し,金属中心の反応性に影響を与えます.
- メソイオンカルベン (MIC) は,有機金属化学における多用途リガンドである.
研究 の 目的:
- カーバゾール構造体と2つのMICリガンドを組み込んだ新しいT形 (LXL) Au (I) -ピンサー複合体を合成し,特徴づけること.
- これらのAu (I) 複合体の反応性,特にプロトン化とアルキル化について調査する.
- 異様なカチオン金種の形成と性質を 探求するためです
主な方法:
- カーバゾール基のピンチャーリガンドの合成
- Au ((I) 前駆体へのリガンドの調整.
- Au ((I) コンプレックスと電ophiles (例えば,陽子,アルキル化剤) の反応.
- NMRスペクトロスコーピー (1H NMRを含む) と潜在的にX線結晶学を用いた特徴付け.
主要な成果:
- カーバゾール核とMICリガンドを備えたT形 (LXL) Au (I) -ピンサー複合体の合成に成功した.
- ステリック因子によって影響される金金属中心またはリガンドにおける電離攻撃 (プロトン化,アルキル化) の実証.
- 黄金で陽子化され,1Hの独特のNMR信号を δ -8.34 ppmで特徴とする独特のカチオン性Au ((III) 水素種の形成.
- Au (III) 水素種の反応性は,水素性ではなくプロティックである.
結論:
- 合成されたT型 (LXL) Au(I) ピンサー複合体は,典型的Au(I) 行動から逸脱する,電友に対する予期せぬ反応性を示す.
- 陽子化により,新しいカチオンのAu (III) 水素が形成され,既知の金属有機化学が拡張される.
- 観測された反応性は,リガンドの設計 (カルバゾールフレームワーク,MIC) が黄金の複合体の電子性およびステリック性に影響を及ぼすことを強調しています.
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