アリルシリルエーサーの金属触媒による転置における地域化学的制御
1Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|June 22, 2006
まとめ
新しい方法により,レニウムヘプトオキシド (Re2O7) を使用したアリルシイロキシ群転置における地域化学を制御する. この戦略では,ビニルボロナートが効率的なトラッピングと,再編成における高キラリティの転送のために使用されます.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- アリル [1,3] 変換反応は,有機合成において根本的な役割を果たします.
- これらの変換における地域化学とキラリティの制御は,依然として重要な課題です.
研究 の 目的:
- シリロキシ群の地域選択性アリル[1,3]転置のための新しい触媒システムを開発する.
- その後のクロスカップリング反応における生成された中間物質の有用性を調査する.
- 再配置中にキラリティの移転の程度を評価するために.
主な方法:
- レニウムヘプト酸化物 (Re2O7) を用いた触媒.
- 同型シリルエーテルとアルキニルボロナートとのアルデルエネ反応によるシス指向ビニルボロナートの生成.
- サイクルボロン酸中間物質を用いたクロスカップリング反応.
主要な成果:
- シリロキシ群のアルリル [1,3]-トランスポーゼーションに対する新しい地域化学的制御が達成されました.
- この戦略は,インシチュートで生成されたビニルボロナートを使用して,アリルヒドロキシル基を効果的にトラップします.
- その結果生じるサイクルボロン酸は,クロスカップリング反応に適しています.
- 酵素濃縮されたアリルシリルエーテルから高いキラリティの移転が観察されました.
結論:
- 開発されたRe2O7触媒化された方法は,地域選択性アリル転置のための新しい経路を提供します.
- このアプローチは,さらなる合成加工のために貴重な循環性ボロン酸中間産物へのアクセスを提供します.
- この方法は,ステレオ化学に対する優れた制御を示し,高いキラリティの転送を可能にします.
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