トリメチラアルミニウムによる鉄触媒誘導C(sp(2)) -HおよびC(sp(3)) -H機能化
Rui Shang1, Laurean Ilies1, Eiichi Nakamura1
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|June 11, 2015
まとめ
この研究では,アルミニウム反応剤と鉄触媒を用いたC-H結合のメチル化のための新しい方法が紹介されています. この効率的なプロセスは,様々なアミド基板に作用し,有機合成のための貴重なツールを提供します.
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:
- C-H結合の機能化は,合成化学の重要な分野である.
- 効率的で選択的なメチル化方法の開発は依然として課題です.
- C-H活性化におけるサイト選択性を達成するために,ディレクティング・グループはしばしば採用されます.
研究 の 目的:
- C ((sp2) -HとC ((sp3) -H結合の直接メチル化のための新しい触媒システムを開発する.
- 様々なアミド基板におけるこのメチル化反応の範囲と限界を調査する.
- C-Hメチル化プロセスの促進における指揮グループの役割を調査する.
主な方法:
- トリメチラアルミニウム (AlMe3) またはそのダイアミン複合体をメチル源として利用する.
- 無機鉄 (III) 塩とディホスフィンのリガンドの触媒量を使用しています.
- 2,3-ジクロロブタンを,触媒サイクルにおけるステキオキシダントとして使用する.
主要な成果:
- 様々なアミド基板におけるC-sp2) -HおよびC-sp3) -H結合のC-Me結合への成功変換.
- (ヘテロ) アリル,アルケニル,およびピコリノイルまたは8-アミノキノイル誘導基を有するアルキルアミドに対する実証された適用性.
- アルミニウム反応剤の温和な性質により,鉄の還元を防ぐため,高い触媒周回数 (最大6500回) を達成しました.
結論:
- 開発された方法は,直接のC-Hメチル化のための効率的で汎用的な経路を提供します.
- 反応の成功のために,指揮グループの使用は極めて重要です.
- この方法論は,有機合成のための触媒C-H機能化の貴重な進歩を提供します.
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