オレフィンにグリニャード剤を空気添加で添加する. アルコールを生成する3つのコンポーネントの結合プロセスの簡単なプロトコルです
Youhei Nobe1, Kyohei Arayama, Hirokazu Urabe
1Department of Biomolecular Engineering, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-59 Nagatsuta-cho, Yokohama, Kanagawa 226-8501, Japan.
Journal of the American Chemical Society
|December 22, 2005
まとめ
グリニャール反応剤は,空気中のオレフィンと反応して,同型アルコールを形成します. この空気媒介反応は,おそらく根本的なメカニズムを含み,新しい合成経路を提供している.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 有機金属化学 有機金属化学
背景:
- グリナード反応剤は,有機合成で広く使用されている多用途の有機金属化合物です.
- オレフィンへの伝統的なグリニャード添加物は,通常,副作用を防ぐために惰性大気下で実行されます.
研究 の 目的:
- 空気大気下でオレフィンに様々なグリニャード反応剤の分子間添加を調査する.
- 同型アルコール形成のための新しい合成経路を探求する.
主な方法:
- シリルメチル,三次アルキル,アルケニル,アリルグリナード反応剤とオレフィン (スタイレン,結合ダイーン,エニン) の反応は,大気圏下で行われます.
- 反応メカニズムを解明するために,惰性大気 (アルゴン) の下で実施された反応との比較研究.
主要な成果:
- 空気の存在下でグリニャード反応剤とオレフィンからホモロゲートされたアルコールの合成を成功させた.
- 反応は酸素を厳格に排除して進行しないことを実証し,急進的な経路を示唆した.
- 代表的な例では, diastereoselectoまたは regioselectivity を良好から優れたレベルまで達成しました.
結論:
- オレフィンへのグリニャード反応剤の分子間添加は,空気によって効果的に媒介することができます.
- 反応は,グリニャール反応剤の空気中酸化によって開始された根本的なメカニズムを通じて進行する可能性があります.
- この方法は,高い選択性を持つ機能性アルコールへの新しい経路を提供します.
関連する概念動画
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