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スタイレンとアミノフェノールによる高度にリガンド制御されたRegioselective Pd-Catalyzed Aminocarbonylation
Tongyu Xu1, Feng Sha1, Howard Alper1
1Centre for Catalysis Research and Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.
Journal of the American Chemical Society
|May 10, 2016
まとめ
この研究では,リガンド制御のパラジアム触媒によるスタイレンのカルボニル化が示され,アミド合成の高い化学的および地域選択性を達成した. リンガンドの選択は線形と枝分かれしたアミド形成を決定し,有機合成における正確な制御を提供します.
科学分野:
- 有機合成
- カタリシス
- 薬剤化学
背景:
- 有機合成における同時に発生する化学反応と地域選択は大きな課題です.
- 移行金属触媒は,リガンド効果を通じて選択性を制御する実行可能な戦略を提供します.
研究 の 目的:
- アミノフェノールとスタイレンをリガンド制御された地域選択的パラジアム触媒カルボニル化するために.
- 選択的に高収量と選択性を持つ線形および分岐型アミドを合成する.
主な方法:
- パラジウム触媒による炭素化反応を用いた.
- 特定のリガンドであるトリス ((4-メトキシフェニル) フォスフィン (L3) と1,3,5,7-テトラメチル-2,4,8-トリオックス-6-フェニル-6-フォスファダマンタン (L5) が使用されている.
- ボロン酸や5-クロロサリシル酸,溶媒 (アセトニトリル,ブタノン) の役割について調査した.
主要な成果:
- スタイレンとアミノフェノールからアミドの化学選択的形成を達成した.
- 線形アミドはアセトニトリルのL3で得られ,枝分かれアミドはブタノンのL5で得られ,両者は高い収量と選択性を持つ.
- リガンド特性 (円角,トールマン電子パラメータ) と反応性,地域選択性との相関.
- 陽子源および対陽子としての酸添加物の反応性および選択性への影響が示された.
結論:
- リガンドの性質は,このパラジウム触媒カルボニレーションにおける地域選択性を決定する重要な要因である.
- この研究は,パラジウム触媒におけるリガンド選択によるアミド構造の制御方法を提供する.
- リンガン効果と添加物の役割を理解することで,有機合成の精度が向上します.
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