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アロマティック化合物のIr-触媒化されたC-Hポリボリレーションを,可逆性を利用して最大容量まで押し上げる
Maria N Eliseeva1, Lawrence T Scott
1Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467-3860, USA.
Journal of the American Chemical Society
|September 6, 2012
まとめ
少量の塩基は,イリジウム触媒による芳香化合物のC-Hポリボリレーションを容易にする. これにより,ペンタキス (pentakis) とコラヌーレン (corannulene) のような高ボリル化分子の合成が,制御された置換剤の位置変更によって可能になる.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- 合成有機化学 合成有機化学について
背景:
- イリジウム触媒によるC-Hボリレーションは,芳香化合物の機能化のための強力なツールです.
- 地域選択性とボリレーションの度合いを制御することは依然として課題です.
研究 の 目的:
- 塩基がIr-触媒化されたC-Hポリボリレーションにおける役割を調査する.
- 高度ボリル化アロマティック化合物を合成する方法を開発する.
主な方法:
- Ir-触媒反応で少量の塩基 (t-ブト酸化カリウムまたはメト酸化ナトリウム) を使用する.
- 過剰なボリル化剤,ビス・ピナコラト・ディボラン (B・2) ピン・2) を利用する.
- 運動的に好ましい製品の均衡を分析する.
主要な成果:
- 塩基は,運動的に好ましいボリレーション産物のバランスを促進する.
- 繰り返しデボリレーション/リボリレーションを行うと,Bpin置換物の位置が変わります.
- 1,3,5,7,9-ペンタキス (Bpin) コランヌレンの高収量,一段階の合成を達成しました.
結論:
- 塩基は,Ir-触媒化されたC-Hポリボリレーションにおいて熱力学的制御を達成するために重要である.
- この戦略は,複雑で高度に置換された芳香系の合成を可能にします.
- ポリボリル化分子を作るためのIr-触媒化されたボリレーションの有用性を拡大する.
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