アリルC-BとアレンC-H結合の銅媒介配列シアネーションは,ヨジドアンモニアムとDMFを用いて行われます
Jinho Kim1, Jiho Choi, Kwangmin Shin
1Department of Chemistry and Molecular-Level Interface Research Center, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
Journal of the American Chemical Society
|January 28, 2012
まとめ
新しい銅媒介法により,容易に入手可能なボロン酸およびエステルを使用して芳香的シアン化が可能になります. この効率的なプロセスは,アレンの地域選択的C-Hシアン化も達成し,合成の可能性を拡大します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成方法論 合成方法論
背景:
- アロマティック化合物は,医薬品や材料の重要な構成要素です.
- アロマティックシステムにシアノ群を導入するための効率的な方法は,非常に求められています.
- 現在のシアネーション方法は,しばしば厳しい条件や特殊な反応剤を必要とします.
研究 の 目的:
- アロマティックボロン化合物の銅媒介による新種の酸化シアネーションを開発する.
- アレンのC-H機能化にこの方法の応用を探求する.
- 反応機構と主要な反応剤の役割を解明する.
主な方法:
- アロマティックなボロン酸,ボロナートエステル,ボラート塩の銅触媒による酸化シアン化.
- ヨウ化物とシアノ窒素の両方の源としてアモニアムヨウ化物を利用しました.
- N,N-ジメチル形式胺 (DMF) は,シアノ群の炭素源として機能した.
- プロトコルを電子に富んだベンゼンに拡張し,直接C-Hシアネーションを行う.
主要な成果:
- 様々な芳香性ボロン誘導体の銅媒介サイアン化に成功しました.
- アレンの地域選択的C-Hシアン化を実証し,シアノ群を直接導入した.
- 最初のヨウ素化に続いてシアン化を含む2段階の反応経路を特定しました.
- ヨウ酸化アンモニアムがヨウ酸化ヨウ酸化物とシアノ窒素の両方を供給する二重の役割を提案した.
結論:
- アロマティックシアネーションのための多用途で効率的な方法を開発した.
- 地域選択的シアネーションのための新しいC-H機能化戦略を確立しました.
- アモニウムヨウ酸化物を含む提案されたメカニズムは,反応経路の洞察を提供します.
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