ボリル・ディクテッド・サイト・セレクティブ・インターモレキュラー・アリル・プロパルギル・C-H・アミネーション
Yuan Liu1, Zhi-Hao Chen1, Yin Li1
1School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou510006, China.
Journal of the American Chemical Society
|July 27, 2022
まとめ
この研究では,α-アミノボロナートを生成するための新しいボリル誘導C-Hアミナート法が導入されています. ボロ酸塩 (B(MIDA) は,高度にサイト選択的な機能化を可能にし,アリルC-H活性化における以前の課題を克服した.
科学分野:
- 有機化学
- キャタリシス
- 合成方法論
背景:
- アリルC-H機能化は,特に類似の陽子で,サイト選択性において課題に直面する.
- 電子陰性原子は地域選択性を助けますが,電陽性原子の戦略は未開発です.
- 現在のα-アミノボロナート合成は,しばしば広範な機能群操作を必要とする.
研究 の 目的:
- 新しいボリル誘導型の分子間C−Hアミネーション反応を開発する.
- α-アミノボロナートの合成において,非常に高いサイト選択性を達成する.
- C−H機能化における指向群としてのボロ酸塩 (B−MIDA) の有用性を探求する.
主な方法:
- アリルとプロパルギルボロナート (B ((MIDA)) の分子間C-Hアミン化.
- N-メチリミノアセチル (MIDA) 保護ボロナートを指向グループとして使用する.
- 広範囲の基板に対する軽い反応条件を用いる.
主要な成果:
- α-アミノボロナート合成において,非常に高い局所選択性 (最大300:1) を達成した.
- 機能化された二次的および三次的α-アミノボロ酸塩の多様な範囲を合成し,優れた収穫量を得ました.
- 隣接する正電荷に対するB (MIDA) 部分の安定効果が示され,高い選択性をもたらした.
- 完全なステレオレテンションが観察され,閉じた移行状態を示唆しています.
結論:
- ボリル誘導C-Hアミナーションは,α-アミノボロナートへの強力で選択的な経路を提供します.
- B (MIDA) グループは,C-H機能化に挑戦することを可能にする,指向とアクティベーションのグループとして機能します.
- 開発された方法は,さらなる合成用途のための多用途のα-アミノボロナートビルディングブロックにアクセスできます.
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