(Z) 異位化されたアリルアルコールの直接的,ステレオ特異的な生成
Sang-Jin Jeon1, Ethan L Fisher, Patrick J Carroll
1P. Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.
Journal of the American Chemical Society
|July 27, 2006
まとめ
新しいワンポット合成により,高度に機能化された (Z) - 代替されていないアリルアルコールは得られます. この方法は,アルキンとアルデヒドを高ステレオ選択性を持つ有価なキラルアルコール製品に効率的に変換します.
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
- ステレオセレクティブ合成
背景:
- アリルアルコールは,有機合成における重要な構成要素である.
- その準備のための効率的でステレオ選択的な方法の開発は,依然として重要な課題です.
- 既存の方法は,多くの場合,複数のステップを必要とし,または広範な基板の範囲が欠如しています.
研究 の 目的:
- (Z) - 置き換えられたアリルアルコールを合成するための新しいワンポット方法を導入する.
- これらの化合物の形成において,高収量とステレオ選択性を達成するために.
- キラルアルデヒドとの反応のダイアステロ選択性を探求する.
主な方法:
- 1-ブロモ-1-アセチレンをダイサイクロヘキシルボランで水酸化する.
- t-BuLiと反応し,伝達し, (Z) 異位化されたビニル亜鉛反応剤の形成.
- ビニル亜鉛反応剤が様々なアルデヒドとインシット反応する.
主要な成果:
- (Z) 異位化されたアリルアルコールの高収量 (81-97%) が得られた.
- 反応は優れたステレオ選択性を示し,ダイアステレオ選択性は6:1から18:1までであった.
- 抗フェルキン剤は主にキラルアルデヒドへの添加で形成された.
結論:
- 開発されたワンポット・メソッドは,高度に機能化された (Z) -非置換性アリルアルコールへの効率的な経路を提供します.
- この方法は,特にキラル基板への添加では,高収量と優れたステレオ制御を提供します.
- このアプローチは,複雑なアリルアルコールの誘導体の合成における重要な進歩を表しています.
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