ニッケル触媒によるアリルフッ化物のスズキ・ミヤウラ反応
Mamoru Tobisu1, Tian Xu, Toshiaki Shimasaki
1Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan. tobisu@chem.eng.osaka-u.ac.jp
Journal of the American Chemical Society
|October 26, 2011
まとめ
新しいニッケル触媒方式は,アリルフッ素とボロンエステルを効率的に結合させる. これらのプロトコルは,金属フッ化物や誘導基を用いたC−F結合を活性化し,有機化学における合成の可能性を拡大する.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- アリルフッ素は医薬品や材料に多く含まれているが,機能化することは難しい.
- クロスカップリング反応は,C−C結合形成の不可欠なツールである.
- 強固なアリルC-F結合の効率的な活性化は,依然として重要な合成障害となっている.
研究 の 目的:
- アリルフッ化物のクロスカップリングのための新しいニッケル触媒プロトコルを開発する.
- 多種多様なアリルフッ化物でスズキ・ミヤウラ反応を可能にするために.
- ニッケル触媒におけるC−F結合活性化メカニズムを調査する.
主な方法:
- 2つの異なるニッケル触媒クロスカップリングプロトコルの開発.
- 一般的なアリルフッ化物結合のために,金属フッ化物の共触媒 (ZrF{4},TiF{4}など) を利用する.
- アリルフッ化物におけるオルト指向群を用いて,サイクロメタレーションによるC−F結合の活性化を促進する.
- N-ヘテロサイクルのスクリーニング (ピリジン,キノリン,ピラゾール,オクサゾリン) を指向グループとして.
- カップリングパートナーに対する置換剤の効果の体系的な研究.
主要な成果:
- スズキ・ミヤウラによる,金属フッ化物共触媒を用いた,電子欠乏性および溶融性芳香性アリルフッ化物の成功結合.
- アリルフッ化物におけるN-ヘテロサイクリック定向群を用いた効率的なクロスカップリングの実証.
- ケトン,エステル,CF(3),アリル,アルケニル群,フルオロナフタレン,フルオロキノリンを含む幅広い基板範囲.
- 様々なオルガノボロンエステルとの成功カップリング.
- ニッケル触媒によるアリルフッ化物クロスカップリングに関する機械学的洞察を得ました.
結論:
- アリルフッ化物のニッケル触媒によるスズキ・ミヤウラ結合のための2つの効果的なプロトコルが確立されています.
- 開発された方法は,クロスカップリング反応におけるアリルフッ化物の有用性を大幅に拡大します.
- 置換物効果を理解することは,C-F債券の活性化メカニズムに関する基本的な洞察を提供します.
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