アルキルアミン・ボランの合成とスズキ・ミヤウラ・クロスカップリング. ボリル・ラジカル による 戦略
Cornelia S Buettner1, Chiara Stavagna1, Michael J Tilby2
1Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany.
Journal of the American Chemical Society
|August 13, 2024
まとめ
この研究は,ボリル基を用いた安定したアルキルオルガノボロン化合物の合成のための新しい方法を導入しています. これらの新しい材料は,スズキ-ミヤウラ交互結合反応に有効であり,従来の方法の代替案を提供します.
科学分野:
- 有機化学
- 有機金属化学
背景:
- アルキルオルガノボロンは,主にスズキ-ミヤウラクロスカップリングを通じて,炭素-炭素結合形成の重要な反応剤である.
- 現在の方法はしばしば2電子プロセスに依存し,アクセシブルなオルガノボロン種の範囲と安定性を制限する.
研究 の 目的:
- アミン結合ボリル基を用いた代替ボリル化戦略を開発する.
- 挑戦的なα-アミノ誘導体を含む新しい,安定したアリファティックオルガノボロンを合成する.
- スズキ-ミヤウラ交互結合反応におけるこれらの新しい化合物の有用性を実証する.
主な方法:
- ボリル基を生成するアミン結合ボランのフォトレドックス酸化とデカルボキシル化.
- ボリルラジカルをスタイレンとイミンに,ラジカル-ポラークロスオーバーで添加する.
- アリルハリドとのスズキ・ミヤウラ交互結合で合成されたオルガノボロン直接適用.
主要な成果:
- プロトデボロネーションに抵抗する,安定した固体アリファティックオルガノボロンの一種が合成された.
- 新しい保護されていないα-アミノオルガノボロン誘導体は,成功裏に準備されました.
- これらのオルガノボロンは,複雑なアリルハライドとのスズキ・ミヤウラ交配に効率的に参加した.
- 処理が難しいアルキルボロン酸の緩やかな放出の可能性を示唆している.
結論:
- 開発されたフォトレドックスボリレーション戦略は,安定したアリファティックなオルガノボロンへのアクセスを提供します.
- これらの新種のオルガノボロンは,複雑な分子合成のためのスズキ-ミヤウラクロスカップリングの有用性を拡張します.
- この方法は,反応性アルキルボロン種を貯蔵して利用するための安定した代替手段を提供します.
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