ゲミナル二炭酸塩は,非対称な合成のためのカルボニルサロゲートとして. パートII. パートII. 適用範囲と応用
Journal of the American Chemical Society
|July 18, 2001
まとめ
新しい非対称性アルキル化法により,アリルゲム-デカルボキシラートからアリルエステルのエナチオセレクティブ合成が可能になりました. このパラジウム触媒反応は,高収量とステレオ選択性を提供し,価値あるキラル構成要素を生み出します.
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
- アシンメトリック・シンセシス
背景:
- アリルエステルは重要な合成中間物質である.
- 合成のためのエナチオセレクティブ・メソッドの開発は,キラル分子へのアクセスに不可欠です.
研究 の 目的:
- アリルエステルの新しいエナンチオセレクティブ合成を開発する.
- 非対称な触媒における前駆体として,アリル基石デカルボキシラートの有用性を調査する.
主な方法:
- パラジアム (((0) カタリストを用いた,キラルリガンド (R,R-1,2-di (((2'-ディフェニルフォスフィノベンザミド) サイクロヘクセン) を用いた,アリル性ジェム・ディカルボキシラートの非対称アルキル化.
- 反応の最適化には,反応性が低い核性粒子の添加速度を遅らせる手順も含まれます.
- 結果となるアリルエステルの後の合成変換.
主要な成果:
- アリルエステルの効率的な合成で,良好な収量.
- マロナト核愛素で達成された高い地域およびエナチオ選択性.
- 適度なエナチオセレクティビティは,反応性が低い核愛素をゆっくり加えることで改善された.
- イソメリゼーション,アルキレーション,クライゼン再配列によるキラリティの新結合への移転が実証されています.
結論:
- 開発された方法は,エナチオメリックに濃縮されたアリルエステルへの効果的な経路を提供します.
- アリル基石二炭酸塩は,ステレオ特異の二重アリル基変換のための多用途のシントンとして機能します.
- この方法論は,キラル性の予測可能な移転を可能にし,複雑なキラル分子を作成します.
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