オレフィンの硫黄アミドおよび弱塩基アニリン酸による水酸化を目的としたプラチナベースの触媒
Dmitry Karshtedt1, Alexis T Bell, T Don Tilley
1Department of Chemistry and Chemical Engineering, University of California, Berkeley, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|September 8, 2005
まとめ
電子性プラチナ (((II) 複合体は,硫黄アミドとアニリンを用いてオレフィンヒドロアミネーションを効率的に触媒化する. この研究では,基板のpKaカットオフを特定し,触媒機構を明らかにし,Pt活性化オレフィン経路を明らかにしました.
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
- 合成化学 合成化学とは
背景:
- ハイドロアミナーション反応は,窒素を含む化合物の合成に不可欠です.
- 水素アミネーションのための効率的な触媒の開発は,有機合成における重要な課題です.
研究 の 目的:
- オレフィンヒドロアミネーションを触媒化する電性プラチナ (((II) 複合体の有効性を調査する.
- この触媒プロセスの基板の範囲とメカニズムの詳細を決定する.
主な方法:
- (COD) Pt (OTf) 2を含むプラチナ (II) 複合体を触媒として使用した.
- 代替アニリンとアリルスルフォナミドを窒素源として使用した.
- NMRスペクトロスコーピー (19F,195Pt) と質量スペクトロメトリを用いた反応中間物質の特徴.
- 速度の法則を確立するために運動学的研究を行いました.
主要な成果:
- 90°Cでアリルスルフォナミドによるオレフィン水素アミネーションで高収量 (>95%) を達成しました.
- 窒素含有基板のpKa切除値 (<1) を実証的に確立しました.
- プロピレンヒドロアミネーションにおけるマルコヴニコフの選択性が実証され,Pt-オレフィン活性化を示す.
- 主要な触媒中間物質[COD]Pt[norbornene]2[OTf]2.2を特定し,特徴づけました.
- 定数法が定数 = k ((obs) [Pt][サルフォナミド] であることを判定した.
結論:
- 電子性Pt(II) 複合体は,硫黄アミドと弱塩基アニリンでオレフィンを水酸化させるのに有効な触媒である.
- 触媒メカニズムは,Pt活性化されたオレフィン種と,速度決定のステップとしてスルフォナミド攻撃を含む.
- この研究は,プラチナ触媒によるヒドロアミネーション反応の範囲とメカニズムに関する貴重な洞察を提供します.
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In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...
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