分子内シリコン補助クロスカップリング反応: 1,3-cis-cisダイエンの単位を含む中規模のリングの一般合成
Scott E Denmark1, Shyh-Ming Yang
1Roger Adams Laboratory, Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|March 7, 2002
まとめ
新しい合成戦略は,環閉メタテシスとパラジウム触媒結合を組み合わせて,ダイエン単位を含む中規模のリングを効率的に作成します. この方法は,複雑な循環型有機分子を合成するための強力な新しい経路を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成方法論 合成方法論
- カタリシス カタリシス カタリシス
背景:
- 中規模のリング (9〜12人のメンバー) の構築は,合成的な挑戦であり続けています.
- 既存の方法には,複雑な構造に対して,効率性や広範な適用性が欠けていることが多い.
研究 の 目的:
- 中型リングの合成のための新しく効果的な方法を開発する.
- ターゲットリングに内部1,3-cis-cisダイエンユニットを組み込む.
- 新しい合成アプローチの範囲と限界を探求する.
主な方法:
- モリブデン催化環閉メタテシス (RCM) と,パラジウム催化,シリコン補助の分子内クロスカップリングの組み合わせを使用した.
- Z-イオドアルケニルテザーを持つアリルアルコールは,シライライスされ,RCMにかけられ,不飽和シロキサンが形成された.
- シロキサンは,テトラブチラモニウムフッ化物と[allylPdCl](2) で活性化され,その後の環閉反応が行われました.
主要な成果:
- 1,3-cis-cis-dieneユニットを含む9,10,11,12個の環を成功裏に合成しました.
- 環閉反応で高収量を達成した.
- 9つ環の不飽和エーテルを合成するための方法論を拡張しました.
- 非常にステレオスペシフィックな分子内結合プロセスを実証しました.
結論:
- 開発された方法は,内部ダイネ単位を備えた中型リングの構築に有効で強力な経路を提供します.
- このプロセスは,ヒドロキシル基の位置づけに柔軟性を提供し,多様なカーボサイクルとヘテロサイクルを合成する可能性を秘めています.
関連する概念動画
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