パラジアム触媒によるアルキル硫酸塩アニオンのアリレーション
Tiezheng Jia1, Mengnan Zhang1, Hui Jiang1
1Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania , 231 S. 34th St., Philadelphia, Pennsylvania 19104-6323, United States.
Journal of the American Chemical Society
|October 14, 2015
まとめ
パラジウム触媒による新しい反応は,アルキル硫酸化物を硫酸塩イオンから効率的に合成します. この方法は,塩基感受性化合物に関連する課題を克服するために,軽度のフッ素誘発戦略を使用します.
科学分野:
- 有機化学
- 有機金属化学
- カタリシス
背景:
- パラジウム触媒によるクロスカップリング反応は有機合成において不可欠である.
- アリルアルキル硫化物の合成は,中間産物の敏感性のために困難です.
- 既存の方法はしばしば,敏感な機能群と相容れない厳しい条件を必要とします.
研究 の 目的:
- アリルアルキル硫酸化物の合成のための新しいパラジウム触媒方法を開発する.
- 硫化物化学における塩基感受性の課題に取り組むこと
- サルフェナートアニオンのアリレーションで高収量と化学選択性を達成する.
主な方法:
- アルキル2− (トリメチルシリル) エチル硫化物のフッ素誘発除去によるアルキル硫酸アニオンの生成.
- アリルブロミドや塩化物を用いたパラジウム触媒によるアリレーション.
- パラジウム触媒を用いたボリュームの高いモノデンテートフォスフィンリガンド (SPhosとCy-CarPhos) を使用する.
主要な成果:
- アリルアルキル硫化物の高収量が得られた.
- この方法は熱分解と塩基誘導除去の問題をうまく克服した.
- アニリンおよびフェノール機能群の存在で優れた化学選択性が観察されました.
結論:
- アルキル硫酸塩アニオンのユニークで効果的なパラジウム触媒のアリレーションが確立されています.
- フッ化物誘発戦略は 価値あるアリルアルキル硫化物へのアクセスを提供します
- この方法論は,幅広い機能群の許容性を提供し,その合成的有用性を拡張します.
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