活性化されたオレフィンのバイオインスピレーションによる触媒E → Zイソメリ化
Jan B Metternich1, Ryan Gilmour1
1Institute for Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|August 28, 2015
まとめ
研究者らは,クマリンのような有価な化合物を合成する重要なステップである活性化オレフィン (Z) の高度選択的 (Z) イソメリゼーションを達成するために, (-) リボフラビンを用いた触媒的方法を開発した.
科学分野:
- 有機化学
- 写真化学
- キャタリシス
背景:
- 複雑なポリエネを活性化するために 自然はフラビンを利用します
- 自然系ではしばしばZからEの異体化が見られる.
研究 の 目的:
- 小分子システムにフラビン媒介活性化を 翻訳する
- 活性化されたオレフィンの高度に (Z) 選択的な触媒性イソメリゼーションを達成する.
- 自然なシステムで観察される異体化方向性を逆転させる.
主な方法:
- オレフィンイソメリゼーションの触媒として (-) リボフラビンを使用.
- 変形した基板のスキャフォールドは,ストレスを誘導する代替剤を加えて切り取ります.
- 反応効率,添加効果,および機械的探査を調査した.
主要な成果:
- オレフィンイソメリゼーションにおける高い (Z) 選択性 (最大99: 1 Z/E) を達成した.
- イソメリゼーションの方向性をE → Zに逆転させました.
- このプロトコルがエノンの基板とクマリン合成に 適用可能であることを実証した.
- 三重エネルギー伝達機構を特定した
結論:
- 操作的にシンプルで,高度に (Z) 選択的な触媒性イソメリゼーションプロトコルを開発した.
- フラビン媒介オレフィン活性化のための小分子パラダイムを確立した.
- キュマリンのような 医学的に重要な基質を合成する 可能性を示した
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