チラル酸を用いたワルフレンツ dearomatization エージェントのエナンチオ濃縮
Andrew W Lankenau1, Diana A Iovan2, Jared A Pienkos1
1†Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
Journal of the American Chemical Society
|February 25, 2015
まとめ
この研究は, dearomatization reagent TpW ((NO) ((PMe3) ((η ((2) -ベンゼン) を分解するための新しい方法を提示しています. このプロセスは,タングステン複合体のキラル分離のために,ディベンゾイルタルタル酸によるダイアステロエーマー塩の形成を活用します.
科学分野:
- 有機金属化学 有機金属化学
- チラルの合成
- カタリシス カタリシス カタリシス
背景:
- Dearomatization反応は,有機合成において極めて重要です.
- オーガノメタリック複合体のキラル分解は,非対称な触媒に不可欠です.
- トングステンの複合体TpW ((NO) ((PMe3) ((η ((2) -ベンゼン) は,多用途の脱塩化反応剤である.
研究 の 目的:
- TpW ((NO) ((PMe3) ((η(2) -ベンゼンのキラル解像度のための方法を開発する.
- この重要な試料のエナチオメリックに純粋な形態へのアクセスを可能にするために.
- トングステンステレオセンターの絶対的構成を決定するための信頼性の高い経路を確立する.
主な方法:
- トングステン複合体の1,3-ジメトキシベンゼン (DMB) アナログの合成.
- 調整されたDMBリガンドをディベンゾイルタルタル酸 (DBTH2) とプロトン化し,ダイアステロエーマー塩を形成する.
- 選択的な降水と単一の二酸化塩の分離.
- デプロトネーションとリガンド交換により,エナティオメリックに濃縮されたTpW ((NO) ((PMe3) ((η ((2) -ベンゼン) が得られます.
- (S) -β-ピネンと2DNMRスペクトロスコピーを用いて絶対的構成の決定.
主要な成果:
- トングステン複合体のDMBアナログの合成が成功しました.
- 単一のダイアステロエーマー塩の選択的な降水により,キラル解像度が可能です.
- TpW ((NO)) ((PMe3) ((η(2) -ベンゼンのエナティオメリックに純粋なRまたはS形態の生産).
- トングステンステレオセンターの絶対的構成を決定する方法の実証.
結論:
- TpW ((NO) ((PMe3) ((η(2) -ベンゼン) のキラル解像度のための実用的で効果的な方法が確立されています.
- この解像度法により,エナチオピュール dearomatization 反応剤にアクセスできます.
- 開発した技術は,ボルンガムの中心における絶対的立体化学の決定を可能にします.
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