軽度な条件下での (ヘテロ) アリルハリドの銅触媒化水酸化
Shanghua Xia1, Lu Gan1, Kailiang Wang1
1Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Lu, Shanghai 200032, China.
Journal of the American Chemical Society
|September 30, 2016
まとめ
銅 (II) アセチラケトネート (Cu (acac) 2) とN,N'-ビス (N,N'-bis) 4-ヒドロキシル-2,6-ジメチルフェニル) オクサラミド (BHMPO) を効率的に水酸化物 (ヘテロ) アリルハリド) として使用する新しい触媒システム. この方法は,温和な条件下での様々な基質の高収量を達成し,フェノールと水酸化ヘテロアレンを合成するための汎用的なアプローチを提供します.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- (ヘテロ) アリルハライドの水酸化は有機合成における重要な変換である.
- 効率的で温和な触媒システムの開発は,活発な研究分野です.
- 銅ベースの触媒は,様々なクロスカップリング反応において有望であることが示されています.
研究 の 目的:
- (ヘテロ) アリルハリドの水酸化のための新しい効率的な触媒システムを開発する.
- 開発された触媒システムの範囲と限界を調査する.
- 軽度な反応条件下でフェノールとヒドロキシル化ヘテロアレンを大量に生成する.
主な方法:
- 銅 (II) アセチラセトネート (Cu) (acac) 2) とN,N'-bis (4-ヒドロキシル-2,6-ジメチルフェニル) オクサラミド (BHMPO) を含む触媒系を使用した.
- 多種多様な (ヘテロ) アリル塩化物,ブロミド,ヨジドの水酸化を調査した.
- 温度と触媒の負荷を含む最適化反応条件
主要な成果:
- 電子ドナーまたは電子引き取りグループを含む様々な (ヘテロ) アリル塩化物を130 °Cでうまく水酸化した.
- より反応性のある (ヘテロ) アリルブロミドとヨジドを低温 (それぞれ80°Cと60°C) で効率的に水酸化する.
- 低銅負荷 (0.5 mol % Cu) で触媒システムの有効性を実証した.
結論:
- Cu ((acac) 2) とBHMPOの組み合わせは, (ヘテロ) アリルハライドの水酸化のための強力で汎用的な触媒システムを表します.
- 方法論は,挑戦的な塩化物を含む幅広い基板に有効です.
- このシステムは,温和な条件下で低触媒負荷で効率的に動作し,合成用途に魅力的です.
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