ステレオ化学的に定義されたアルファ-スルフォナミドの静かな結合は,オルガノスタニノスタニノスである
Kevin W Kells1, J Michael Chong
1Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Journal of the American Chemical Society
|December 2, 2004
まとめ
この研究では,トリビュチルスタニル金属およびアリアルデヒドを用いたアルファ-スルフォナミドスタナンの合成のための新しい方法が紹介されています. その結果生成された化合物は静止結合を経て,高いダイアステロ選択性と構成逆転を示します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成化学 合成化学とは
- 有機金属化学 有機金属化学
背景:
- サルフォナミドは,医薬品化学における重要な機能群である.
- 静かな結合は,炭素-炭素結合形成反応の重要な反応である.
- キラル化合物のステレオセレクティブ合成は,依然として大きな課題です.
研究 の 目的:
- アルファ-スルフォナミドスタナンヌスへの新しいステレオ選択経路を開発する.
- パラジウム触媒によるクロスカップリング反応におけるこれらの中間物質の有用性を調査する.
- 合成変換のステレオ化学的結果を調査する.
主な方法:
- アリアルデヒドの (R) - テルト-ブタネスルフォニミン誘導体にトリビュチルスタニル金属を添加する.
- m-CPBAを用いた中間アルファ-スルフィナミドスタナンの酸化.
- パラジウム/銅で触媒化されたベンゾイル塩化物によるスティル型結合は,トリソル2,4,6-トリメトキシフェニル) フォスフィンリガンドを使用しています.
主要な成果:
- アルファ-スルフィナミドスタノスタナンの形成において,高いダイアステロ選択性 (>98%de) が達成される.
- 酸化によるアルファ-サルフォナミドスタナンの成功合成.
- 効率的なStilleカップリングにより,ベンジル炭素の配置の逆転により,望ましい製品が得られます.
結論:
- アルファ-スルフォナミドスタナン類を合成するための堅牢でステレオ選択的な方法が確立されています.
- 開発された中間物質は,静止結合反応に価値があります.
- 反応は,ベンジル基の位置でのステレオ化学の予測可能な逆転とともに進みます.
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