ディヒドリド ((phosphinooxazoline)) イリジウム複合体の実験と計算を組み合わせた研究
Clément Mazet1, Sebastian P Smidt, Markus Meuwly
1Departments of Organic Chemistry, St. Johanns Ring 19, and Physical Chemistry, Klingelbergstrasse 80, Basel University, CH-4056 Basel, Switzerland.
Journal of the American Chemical Society
|October 28, 2004
まとめ
チラルフォスフィノオクサゾリンイリジウム複合体は二水素と反応して,ステレオ選択性二水素複合体を形成する. リガンド構造は,ステリック効果と電子効果によって誘発される同位体エネルギーと形成に大きく影響する.
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
- ステレオ化学 ステレオ化学
背景:
- イリジウム複合体とキラルリガンドは,非対称合成において極めて重要です.
- 反応性とステレオ選択性に対するリガンドの影響を理解することは,触媒設計の鍵です.
研究 の 目的:
- ダイヒドロゲンとキラル[PHOX]Ir[COD][+]複合体の反応を調査する.
- ディヒドリド複合体の形成を左右するステレオ化学的結果と要因を解明する.
主な方法:
- 反応を監視し,ステレオ化学を割り当てるために,核磁気共鳴 (NMR) スペクトロスコーピーを用いる.
- 密度関数理論 (DFT) の計算により,同位体構造とエネルギーが決定される.
主要な成果:
- 最初,単一の二水素同位体を形成し,さらなる反応でダイアステロエーマーが続く.
- NMRデータは,3つのヒドリド複合体のステレオ化学的割り当てを可能にしました.
- DFTの計算は,立体同位体間の有意なエネルギー差を明らかにし,リガンドの影響力を強調しました.
結論:
- キラル・フォスフィノオクサゾリン・リガンドは,二水素複合体のステレオ選択的形成に強く影響する.
- PHOXリガンドのステリックおよび電子因子は,ヒドリド添加を決定し,トランス-Ir-N構成を好む.
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