カタリティック・ヒドロチオレーション:対照制御された地域選択性
Xiao-Hui Yang1, Ryan T Davison1, Shao-Zhen Nie1,2
1Department of Chemistry , University of California , Irvine , California 92697 , United States.
Journal of the American Chemical Society
|February 9, 2019
まとめ
この研究では,ロジウムのカウンターイオンによる地域選択性を制御するダイエンの触媒性水溶解が詳細に示されています. この方法により,β-ファルネシンから (-) -アゲラシジンAを初めてエナンチオセレクティブに合成することができる.
科学分野:
- 有機金属化学
- カタリシス
- 有機合成
背景:
- 1,3-ダイエンの触媒性水酸化は,アリル硫化物とホモアリル硫化物の合成に不可欠である.
- これらの反応における地域選択性を制御することは依然として大きな課題です.
研究 の 目的:
- 1,3-ダイエンの触媒性水溶解を拡大する.
- アリル酸またはホモアリル酸硫化物の形成において高い地域制御を達成する.
- (-) - アゲラシジンAの第1回エナント選択合成を可能にします.
主な方法:
- 異なるカウンターイオン (例えば,SbF6−,Cl−) を含むロジウム (Rh) 複合体を利用した.
- 異なるダイネの調整モード (η4対η2) を含むメカニズム的経路が調査された.
- エッセンシャルオイルの成分であるβ-ファルネセンのヒドロチオル化.
主要な成果:
- 地域選択性はRhカウンターによって決定され,非調整カウンターはアリル硫化物 (η4調整) を好み,調整カウンターはホモアリル硫化物 (η2調整) を好む.
- マルコビニコフ経路と反マルコビニコフ経路の分数および逆のチオール依存性を合理化するメカニズムを提案した.
- (-) アゲラシジンAの合成が成功しました.
結論:
- カウンテリオンの選択は,Rh触媒による1,3-ダイエンの水酸化における地域選択性の重要な決定因子である.
- 異なるヒドロチオレーション経路におけるチオール依存のメカニズム的理解を開発した.
- (-) - アゲラシジンAのエナチオ選択的合成のための新しい経路を確立した.
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