カップリング N-H デプロトン化,C-H アクティベーション,および酸化:無金属C ((sp3) -H アミネーションと無保護アニライン
Christopher J Evoniuk1, Gabriel Dos Passos Gomes1, Sean P Hill1
1Florida State University , Tallahassee, Florida 32306, United States.
Journal of the American Chemical Society
|October 18, 2017
まとめ
この研究では,保護されていないアニリンと分子酸素によるt-BuOKを用いた分子内酸化C-Hアミネーションの軽い方法が導入されています. このプロセスは,シネジスティックなベース,ラジカル,酸化作用によって,移行金属のないN-ヘテロサイクルを効率的に合成します.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- 酸化C−Hアミネーションは窒素を含む化合物の合成に不可欠である.
- 既存の方法は,しばしば厳しい条件,移行金属,または事前機能化された基板を必要とする.
研究 の 目的:
- 新しく軽度で金属のない分子内酸化C-Hアミネーション反応を 開発する.
- 簡単に手に入る材料から多様なN-ヘテロサイクルを合成する.
主な方法:
- 塩基として tert-butoxide (t-BuOK),酸化剤として分子酸素,溶媒として N,N-dimethylformamide (DMF) を利用した.
- 保護されていないアニリンとC ((sp3) -H結合を伴う,結合解離エネルギー (BDE) が85kcal/mol未満の反応を調査した.
- 反応のメカニズムとエネルギー環境を明らかにするために計算化学を使用した.
主要な成果:
- 温和な条件下で効率的な分子内酸化C-Hアミネーションを達成した.
- 小分子から拡張アロマティックまで,幅広い範囲のN-ヘテロサイクルを成功裏に合成した.
- 移行金属や強い酸化物質なしで反応の適用性を実証した.
結論:
- 開発された方法は,C-N結合形成のための多用途で持続可能なアプローチを提供します.
- 基本的,急進的,酸化する種間のシナジーが 反応のカスケードを駆動する.
- 選択的な脱プロトネーションは,このプロセスの主要な原動力として特定されています.
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