アルコキシボレーション:アルキネス間のB-O σ結合の環閉添加
Joshua J Hirner1, Darius J Faizi, Suzanne A Blum
1Department of Chemistry, University of California, Irvine , Irvine, California 92617-2025, United States.
Journal of the American Chemical Society
|March 5, 2014
まとめ
研究者らは新しいアルコキシボレーション反応を開発し,アルキンにボロン-酸素結合を加えるようにした. この突破は,合成のための有価な酸素を含むオルガノボロン化合物への直接的なアクセスを提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 有機金属化学 有機金属化学
背景:
- オーガノボロン反応剤は,通常,炭素-炭素多重結合にボロン-Xシグマ結合を加えることで合成されます.
- 強いボロン-酸素結合は,歴史的に,添加反応のための直接の活性化を防止し,酸素を含むオルガノボロン化合物へのアクセスを制限しています.
研究 の 目的:
- ボロン-酸素シグマ結合をアルキンに直接添加するための新しいアルコキシボレーション反応を開発する.
- 酸素を含むオルガノボロン反応剤を合成するための軽度かつ機能群耐性の方法を確立する.
主な方法:
- ボロン-酸素シグマ結合を活性化するために,ゴールド触媒戦略を利用した.
- ボロン-酸素シグマ結合を様々なアルキンに添加することを研究した.
主要な成果:
- アルコキシボレーション反応を成功裏に実現し,アルキンにボロン-酸素シグマ結合の添加を達成しました.
- 生産された機能化されたO-ヘテロサイクリックボロン酸誘導体.
- 幅広い機能群の互換性と軽度の反応条件が実証されています.
結論:
- 開発された金触媒アルコキシボレーションは,酸素を含むオルガノボロン反応剤への新しい直接的な経路を提供します.
- この方法は,ボロン-酸素結合活性化に関連する以前の制限を克服しています.
- 合成された化合物は,異なる合成アプリケーションの可能性を秘めています.
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