コバルト触媒によるα-置換アクリラートのエナンチオセレクティブ水酸化
Manoj D Patil1, Kiron Kumar Ghosh1, T V RajanBabu1
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States.
Journal of the American Chemical Society
|March 3, 2024
まとめ
この研究は,α-アルキルおよびα-アリルアクリラートのための新しいコバルト触媒水酸化を導入し,複雑な分子合成のための貴重なキラルシントンを作成します. この方法は,穏やかな条件下で高い地域およびエナチオ選択性を提供します.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- 金属触媒によるエナンチオセレクティブ水酸化は,α-アルキルアクリル酸誘導体にとって極めて重要であるが,しばしばロジウム触媒を必要とする.
- α-アリラクリル酸エステルの非対称な水酸化は未調査のままである.
- 大規模な有機的変異には 地球に豊富な触媒が必要である.
研究 の 目的:
- 地球に豊富に存在するコバルト触媒を用いて,α-アルキル-およびα-アリル-アクリラートの効率的で高度な地域およびエナチオ選択的水酸化を開発する.
- この変換のための軽い反応条件を確立する.
- 生成されたβ-ボリレイテッドプロピオネートのキラルシントンとしての有用性を実証する.
主な方法:
- コバルト触媒を用いた2−−ダイアリルフォスフィノフェニル) オクサゾリンのリガンドを使用した.
- 軽度な条件下でα-アルキル-およびα-アリル-アクリラートの水酸化を行った.
- カチオンの Co ((I) 種を含むメカニズム的研究を行い,反応経路を提案した.
主要な成果:
- α-アルキル-およびα-アリル-アクリラートの効率的で高度な地域およびエナチオセレクティブな水酸化が達成され,β-ボリル化プロピオネートが得られる.
- "ロシュ"エステルと高収量とエナチオ選択性を持つ熱酸エステルを製造することによって,合成の有用性を実証した.
- 機理学的な研究は,活性な触媒としてカチオン性Co ((I) 種を確認し,酸化的移行機構を提案した.
結論:
- コバルト触媒によるアシンメトリック水溶解を広く適用できる新技術を開発した.
- その結果生じるキラルβ-ボリレートプロピオネートは,プロピオネートを含むモチーフを合成するための多用途の中間物質である.
- この方法論は"ロシェ"エステルや熱帯酸エステルなどの重要なキラル構成要素への効率的なアクセスを提供します.
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