強い濃縮酸は,単純なディビニルケトンの触媒的非対称なナザロフサイクルを可能にします
Jie Ouyang1, Jennifer L Kennemur1, Chandra Kanta De1
1Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany.
Journal of the American Chemical Society
|February 16, 2019
まとめ
この研究では,サイクロペンテノンの生成のための新しい触媒的非対称なナザロフ循環法が導入されています. このプロセスは強いイミドディフォスフォリミダートブレンステッド酸を使用し,高収量とエナチオピュア製品の選択性を達成します.
科学分野:
- 有機化学
- 非対称な触媒
背景:
- ナザロフ循環は,サイクロペンテノンの合成のための重要な反応である.
- この変換のための効率的な非対称的な方法の開発は,キラルビルディングブロックにアクセスするために不可欠です.
研究 の 目的:
- 単純な,非循環的,アルキル置換のディビニルケトンの新しい触媒的非対称なナザロフサイクルを報告する.
- この変換において,新たに開発された強固で閉じ込められたイミドディフォスフォリミド酸の有用性を実証する.
主な方法:
- 強力で閉じ込められたイミドディフォスフォリミデートブロンステッド酸を触媒として使用する.
- シンプルな,アサイクリックな,アルキル置換されたディビニルケトンを基板として使用する.
主要な成果:
- 単環サイクロペンテノンの合成に成功
- サイクリング製品における優れた地域,ダイアステレオ,およびエナチオ選択性を達成した.
- 化学的有用性を証明した.
結論:
- 開発された触媒システムは,エナチオピュアなサイクロペンテノンへの効率的な経路を提供します.
- 強固で閉じ込められたイミドディフォスフォリミド酸は,非対称なナザロフ循環の効果的な触媒である.
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A titration is carried out for 25.00 mL of 0.100 M HCl (strong acid) with 0.100 M of a strong base NaOH. The pH at different volumes of added base solution can be calculated as follows:
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